aba16vt Posted March 23, 2011 Report Share Posted March 23, 2011 ok so i have my quest running pretty good i took it for a spin a couple of days ago and it was making boost just fine. tonight i took it for a spin and the second it starts to make any kind of boost i get fuel/spark cut. the only thing i have messed with between then and now is the timing and i hooked the vacume line back up to the blow off. a basic description of what its doing is when i start off if first it revs up and then just dumps, i let off the gas and it starts running normal again what gives???? some input would be greatly appriciated i dont know much about these cars yet Link to comment Share on other sites More sharing options...
MikeMeyerhoff Posted March 23, 2011 Report Share Posted March 23, 2011 Ignition timing has to be right for the car to run well. You say you've got fuel cut, but too much timing can also create a misfire that seems like a fuel cut. What exactly did you do when you "messed with the timing" ? The stock vacuum advance should also retard timing under boost. Make sure your lines are connected properly and there is are no leaks. Check it using a mighty vac's pressure side. If if won't hold pressure, fix it. Link to comment Share on other sites More sharing options...
aba16vt Posted March 23, 2011 Author Report Share Posted March 23, 2011 this was no mis fire, it was my foot on the gas and everything just quit kinda thing like the motor was off. by mess with the timing i mean i set the timing. last time i drove it the timing was just in the ball park. i may have set it wrong. i set the timing to about 10 degrees with the vacume line discontected, with it reconnected it pulled the timing up. give it some gas and it backs the timing off. working like its supposed to as far as i can tell. one thing i forgot to mention is that the idle was rather high with the timing set so i turned the idle screw to bring it down, the car was still very responsive to the throttle, idled great, ran great up until it was about to make boost. i probably should have double checked the timing at that point to make sure it was still right. i dont see that giving me a fuel cut issue though. Link to comment Share on other sites More sharing options...
The Rabbit1 Posted March 23, 2011 Report Share Posted March 23, 2011 was it at operating temp? mine does that sometimes if it is still cold. Link to comment Share on other sites More sharing options...
aba16vt Posted March 23, 2011 Author Report Share Posted March 23, 2011 yeah the car was pretty warmed up. i just found it odd since it had never done that before. any other thoughts? Link to comment Share on other sites More sharing options...
Caliber308 Posted March 23, 2011 Report Share Posted March 23, 2011 (edited) At what boost? Also, once you mess with the ISC adjustment screw you will have to do the ISC/TPS reset again. You just threw everything out of wack.Have you checked for the following:Boost leak at the couplers? A disconnected vacuum line? Injector malfunction? Fuel pump malfunction? Fuel filters?If you have a Fuel Pressure Gauge installed, What is the pressure at idle and on boost? Do you have a Wideband 0-2? If so, what is your A/F Gauge reading when this problem occurs. Bill Edited March 23, 2011 by Caliber308 Link to comment Share on other sites More sharing options...
aba16vt Posted March 24, 2011 Author Report Share Posted March 24, 2011 At what boost? Also, once you mess with the ISC adjustment screw you will have to do the ISC/TPS reset again. You just threw everything out of wack.Have you checked for the following:Boost leak at the couplers? A disconnected vacuum line? Injector malfunction? Fuel pump malfunction? Fuel filters?If you have a Fuel Pressure Gauge installed, What is the pressure at idle and on boost? Do you have a Wideband 0-2? If so, what is your A/F Gauge reading when this problem occurs. Bill cool thanks Bill, yeah after thinking about it for a while i came to the realization it might have something to do with the isc screw and tps. i havent had a chance to check it yet though. it basicly does it at what im guessing is about to be 1 pound of boost i dont have a wide band on it but if i dont figure this out im yanking the stock stuff and going straight to the stand alone. i know how that works! i was just hoping to drive this thing in stock form while i make a multiport manifold for it. no boost leaks vacume lines are all connected or pluged (last time i drove it had 4 open and ran great what is the correct tps voltage seting at closed throttle? and what is the correct way to set the isc screw? im not Familiar with that at all Link to comment Share on other sites More sharing options...
The Rabbit1 Posted March 24, 2011 Report Share Posted March 24, 2011 cool thanks Bill, yeah after thinking about it for a while i came to the realization it might have something to do with the isc screw and tps. i havent had a chance to check it yet though. it basicly does it at what im guessing is about to be 1 pound of boost i dont have a wide band on it but if i dont figure this out im yanking the stock stuff and going straight to the stand alone. i know how that works! i was just hoping to drive this thing in stock form while i make a multiport manifold for it. no boost leaks vacume lines are all connected or pluged (last time i drove it had 4 open and ran great what is the correct tps voltage seting at closed throttle? and what is the correct way to set the isc screw? im not Familiar with that at all.48-.52 http://www.starquestclub.com/forum/index.php?showtopic=28069 Link to comment Share on other sites More sharing options...
aba16vt Posted March 24, 2011 Author Report Share Posted March 24, 2011 thanks! i cant seem to ever find what im looking for when i do a search on this site. Link to comment Share on other sites More sharing options...
Indiana Posted March 24, 2011 Report Share Posted March 24, 2011 this was no mis fire, it was my foot on the gas and everything just quit kinda thing like the motor was off. by mess with the timing i mean i set the timing. last time i drove it the timing was just in the ball park. i may have set it wrong. i set the timing to about 10 degrees with the vacume line discontected, with it reconnected it pulled the timing up. give it some gas and it backs the timing off. working like its supposed to as far as i can tell. one thing i forgot to mention is that the idle was rather high with the timing set so i turned the idle screw to bring it down This isn't right. 10btdc is two marks to the left of the TDC mark as you are looking at it from the front of the engine. You reconnect the vac. reference hose to the vac. adv. and it advances timing further your throttle plate is too far open, meaning its idling too high from the position of the throttle plate and/or the timing. You don't then lower it by turning that screw because its the timing that had it higher but you do have to check that again, plus the TPS and then the timing again and when you're done no it won't matter if that hose is on or not. You give it gas and it backs timing off? No, it should increase it. If the throttle cable was ever tight during any of that the idle motor wasn't going to move anyway. Loosen it way up, its to be slack at idle anyway don't worry there's plenty left to get wide open throttle when you mash the gas but that has to be slack at idle and has enough slack so that when the idle motor does move it won't tighten it up again. You have to get that fixed idle screw backed out before you start so that its not preventing the idle motor from going in to the point you can't get into range for the MPS then you set it back the last thing. Timing too far advanced and you get into boost the knock sensor might have went off causing that or your secondary injector clip is dirty or loose. http://www.b2600turbo.com/images/IM002985.JPG Link to comment Share on other sites More sharing options...
aba16vt Posted March 24, 2011 Author Report Share Posted March 24, 2011 (edited) This isn't right. 10btdc is two marks to the left of the TDC mark as you are looking at it from the front of the engine. You reconnect the vac. reference hose to the vac. adv. and it advances timing further your throttle plate is too far open, meaning its idling too high from the position of the throttle plate and/or the timing. You don't then lower it by turning that screw because its the timing that had it higher but you do have to check that again, plus the TPS and then the timing again and when you're done no it won't matter if that hose is on or not. You give it gas and it backs timing off? No, it should increase it. If the throttle cable was ever tight during any of that the idle motor wasn't going to move anyway. Loosen it way up, its to be slack at idle anyway don't worry there's plenty left to get wide open throttle when you mash the gas but that has to be slack at idle and has enough slack so that when the idle motor does move it won't tighten it up again. You have to get that fixed idle screw backed out before you start so that its not preventing the idle motor from going in to the point you can't get into range for the MPS then you set it back the last thing. Timing too far advanced and you get into boost the knock sensor might have went off causing that or your secondary injector clip is dirty or loose. http://www.b2600turbo.com/images/IM002985.JPG ok let me see if im following, so is 10 degrees initial ok? but when i put the vac lin on its not supposed to bring the timing up much or at all?? the idle was way high so i did need to back it off but i also understand i need to set the timing again since i have now adjusted airflow. i set the timing at 10 and when i connected the vac line the timing mark went to about the middle of the motor while i was watching it. which brought the rpm up more. so where should the timing set whith the vac line connected and the motor idling properly? and with the motor idling at 1200-1300 when i gave it gas the timing would back off. which i found odd too. i did make sure to have slack in the throttle cable so i could back the throttle down i will just have to mess with it some more and the part in bold im not following if you can please go more indept on that i would greatly apriciate it. so there are two screws on the TB one is for the throttle plate and i take it the other one goes to the motor your talking about? also what does MPS stand for Edited March 24, 2011 by aba16vt Link to comment Share on other sites More sharing options...
Indiana Posted March 24, 2011 Report Share Posted March 24, 2011 If you hooked up the hose and it moved to the middle mark it sounds like you have it set at 10ATDC not 10BTDC where it should be. If it moved from 10BTDC to TDC that is retarding the timing and the vac. adv. can't do that (unless its positive boost pressure and its not going to have that while idling) The distributor might be off one tooth have you ever checked that? Take the dist. cap off and you have your TDC mark lined up the distributor only after turning the engine clockwise and don't turn it counter clockwise or the slack in the timing chain will cause it to be off since the oil pressure puts tension on the plunger from the side of the pump to keep the chain tight. You must have the rotor pointing like this to start out with if not its off and you need to pull it out, twist the rotor a little bit and stick it back in and since the gears mesh in a way that causes the shaft to turn you stab it off from how it is shown when you first insert it. You are supposed to use a little dot and mark but still unless you get that lined up and the chain and deck surfaces aren't OEM spec it won't work anyway you'll still be off one tooth. http://www.b2600turbo.com/images/IM009364a.JPG Link to comment Share on other sites More sharing options...
JAinsworth Posted March 24, 2011 Report Share Posted March 24, 2011 thanks! i cant seem to ever find what im looking for when i do a search on this site. TPS/ISC reset can be found here: http://www.starquestclub.com/forum/index.php?showtopic=28069Jimmy Link to comment Share on other sites More sharing options...
aba16vt Posted March 25, 2011 Author Report Share Posted March 25, 2011 If you hooked up the hose and it moved to the middle mark it sounds like you have it set at 10ATDC not 10BTDC where it should be. If it moved from 10BTDC to TDC that is retarding the timing and the vac. adv. can't do that (unless its positive boost pressure and its not going to have that while idling) The distributor might be off one tooth have you ever checked that? Take the dist. cap off and you have your TDC mark lined up the distributor only after turning the engine clockwise and don't turn it counter clockwise or the slack in the timing chain will cause it to be off since the oil pressure puts tension on the plunger from the side of the pump to keep the chain tight. You must have the rotor pointing like this to start out with if not its off and you need to pull it out, twist the rotor a little bit and stick it back in and since the gears mesh in a way that causes the shaft to turn you stab it off from how it is shown when you first insert it. You are supposed to use a little dot and mark but still unless you get that lined up and the chain and deck surfaces aren't OEM spec it won't work anyway you'll still be off one tooth. http://www.b2600turbo.com/images/IM009364a.JPG no with the vac line on it didnt move to the middle timing mark it moved counter clockwise to the middle of the block, like tons of advance. as far as the timing backing off under throttle i watched the timing more closely last night after doing whats listed below and it just backs off for a second when the vac drops and then climbs back up. that picture was worth a head ache or two, i was having major issues with the distributor not having enough range to bring the car into proper timing even moving teeth and i suspected i was off a tooth on the cam gear. after seeing that and knowing forsure where the cap was supposed to point i was certain it was the timing chain so i pulled the cam gear and fixed that now everything lines up correctly. so with all the timing corrected and the vac line disconnected it runs much better and holds 10btdc as soon as i connect vac advance goes way up and runs poor from all the timing, i will need to do the tps/ics settings and see where it lands. also if the computer is sensing knock does it do a fuel cut?thanks everyone for all the input so far Link to comment Share on other sites More sharing options...
Indiana Posted March 25, 2011 Report Share Posted March 25, 2011 (edited) You must have that vac. adv. hose on the wrong port in the throttlebody. There are three in a row on the driver side and the vac. adv. hose goes on the forward most one. The passage through the throttlebody has the tiny opening inside just above the throttleplate at idle so there's no vacuum while idling hot when you are setting this all up meaning if you put that hose on, NOTHING is to happen. No, there's not a "fuel cut" on 87+ cars because that has to come from the boost pressure sensor mounted on the firewall that only the 83-86 fuel systems use. What all hoses are hooked up to that throttlebody and where do they go? Only two are necessary, the one for the vac. adv. and the short one for the fuel pressure regulator. In the driver side edge of the intake manifold is the hose that goes along the firewall for the hvac system to be able to move the doors in the heater box and for the cruise. There's a hose from your wastegate actuator to the intercooler plumbing. Unused ports can't be left open with the exception of one of the three on the 88/89 WG actuator if you have that. Now the harder part that you just changed needs checked, you shouldn't have just moved the cam gear there's a different way to check that. Assuming the block and head decks haven't been milled down quite a bit this is true, otherwise the line through the gear will end up a little more to the passenger side. With the crankshaft pulley mark and the timing cover TDC mark lined up look at the cam gear dowel pin hole. Only turn clockwise as the tension from the oil pump for the timing chain will go a bit slack and the cam won't rest where its supposed to so if you do have to turn it a tiny bit counter clockwise just go a little past then come back to line up those marks only turning clockwise. It has to be at the top or you're half turn off so turn the crankshaft one more revolution. A line drawn through the cam gear mounting bolt hole, the dowel pin hole and out to the gear teeth intersects between two gear teeth tips. The tip of the tooth to the driverside of that line will intersect with a line drawn through the two mounting holes in the cam tower caps for the valve cover. This has nothing to do with setting up the distributor or setting ignition timing, this is CAM timing. Cam timing in regards to the crankshaft, not ignition. It may have been off and you corrected it or it wasn't and you messed it up so you need to pull the valve cover back off and check this. You should have been able to do what you did by just moving the dist. drive gear in reference to the cam drive gear without having to move the timing chain. http://www.b2600turbo.com/images/IM003019.JPG Edited March 25, 2011 by Indiana Link to comment Share on other sites More sharing options...
aba16vt Posted March 25, 2011 Author Report Share Posted March 25, 2011 (edited) ok so i think i have the distributor plugged into the wrong port. and those are the only two that are hooked up all the egr stuff is removed. well i am the one who put it back together a tooth off, i replaced the head gasket a while back and there is such a small amount of movement in the cam gear when turning the crank that when i put it back together it looked correct until i saw the photo of the distributor you posted. i know your thinking why did i pull the cam gear out since i didnt need to to do the head gasket. long story short the car was roled in gear with the head off which bent the bracket that holds the cam gear so i had to take it off to get that bracket out. had i actualy drawn a line up the cam gear it may have shown i put it back together wrong. the main issue i was having with the distributor was because the cam gear was off, no matter which tooth i used to set the distributor it didnt have enough rotational movement to set the initial timing correctly. i was hitting the stud just to get 10 degrees. with it set now i can get 10 degrees with the dist stud almost in the middle. Edited March 25, 2011 by aba16vt Link to comment Share on other sites More sharing options...
aba16vt Posted March 28, 2011 Author Report Share Posted March 28, 2011 ok so everything is back together and the car idles pretty cherry. i am still running into fuel issues still which i have narrowed down the the secondary injector. i have plugged the primary fuel injector plug into it to ensure its still working and it is. so something is happening between the ecu and the injector plug. when i take the car out for a spin it runs fine as soon as i get to about 1800-2000 rpm it just falls on its a$s untill it gets back down to like 1500 rpm. it will also cut out on a high rev when its parked i will rev it up and when i let off the gas peddle and then pump it again it doesnt do anything untill it gets back down to a lower rpm. i feel like it has something to do with boost but i dont know. any thoughts on this issue?? Link to comment Share on other sites More sharing options...
Indiana Posted March 28, 2011 Report Share Posted March 28, 2011 TPS might be bad. Put your volt meter on it and slowly move the throttle and it should change voltage steady no jerks or dead spots. Link to comment Share on other sites More sharing options...
Indiana Posted March 28, 2011 Report Share Posted March 28, 2011 If someone put new clips on there, unwrap them and see if you have a broken connection covered up by tape or something. With the ignition key "ON" you'll have battery voltage on one of the wires in each clip. If someone has had the ECU in and out, sometimes one of those connectors doesn't go up in all the way and snap, push on it and see or unplug and plug it back in again. Link to comment Share on other sites More sharing options...
aba16vt Posted March 28, 2011 Author Report Share Posted March 28, 2011 sounds good! i unwrapped the wiring to the injector plugs down to where it goes into the harness but i need to cut the shrink tube off the wire to look at it. i got fed up and made some dinner instead. i didnt think to check the plug for voltage i will do that. thanks again Link to comment Share on other sites More sharing options...
aba16vt Posted March 28, 2011 Author Report Share Posted March 28, 2011 well i have voltage to both plugs, i will have to chase the other wire and see what its doing Link to comment Share on other sites More sharing options...
aba16vt Posted March 30, 2011 Author Report Share Posted March 30, 2011 You must have that vac. adv. hose on the wrong port in the throttlebody. There are three in a row on the driver side and the vac. adv. hose goes on the forward most one. The passage through the throttlebody has the tiny opening inside just above the throttleplate at idle so there's no vacuum while idling hot when you are setting this all up meaning if you put that hose on, NOTHING is to happen. No, there's not a "fuel cut" on 87+ cars because that has to come from the boost pressure sensor mounted on the firewall that only the 83-86 fuel systems use. ok so the title says 87 but the plate in the door says manufactured in 86 so which is it? is it possible that i have that sensor in my car? what does it look like? Link to comment Share on other sites More sharing options...
aba16vt Posted April 1, 2011 Author Report Share Posted April 1, 2011 so i had a chance to try and set the tps and ics. something isnt right fully warmed up the ics is still reading 2.24 volts do i have a bad temp sensor? and when i checked the tps it was reading like .09 so i tried to adjust it and all i could get out of it turned fully clockwise was .26v. the idle is sitting at about 850-900 fully warmed up and i do think the ics is working, the idle is much higher on initial cold start. so someone tell me what im doing wrong or what you might think im doing wrong. Link to comment Share on other sites More sharing options...
StarquestRescue Posted April 1, 2011 Report Share Posted April 1, 2011 ok so everything is back together and the car idles pretty cherry. i am still running into fuel issues still which i have narrowed down the the secondary injector. i have plugged the primary fuel injector plug into it to ensure its still working and it is. so something is happening between the ecu and the injector plug. when i take the car out for a spin it runs fine as soon as i get to about 1800-2000 rpm it just falls on its a$s untill it gets back down to like 1500 rpm. it will also cut out on a high rev when its parked i will rev it up and when i let off the gas peddle and then pump it again it doesnt do anything untill it gets back down to a lower rpm. i feel like it has something to do with boost but i dont know. any thoughts on this issue?? so i had a chance to try and set the tps and ics. something isnt right fully warmed up the ics is still reading 2.24 volts do i have a bad temp sensor? and when i checked the tps it was reading like .09 so i tried to adjust it and all i could get out of it turned fully clockwise was .26v. the idle is sitting at about 850-900 fully warmed up and i do think the ics is working, the idle is much higher on initial cold start. so someone tell me what im doing wrong or what you might think im doing wrong.Sound like your isc motor position sensor is bad, probably the nose switch portion as well. If you disconnect one or both of the plugs. I do not remember which one. the problems should go away. You will have to play with the gas pedal till it warms up though. Link to comment Share on other sites More sharing options...
StarquestRescue Posted April 1, 2011 Report Share Posted April 1, 2011 http://www.starquestclub.com/forum/index.php?showtopic=106590&st=0&p=1036028&fromsearch=1entry1036028 Be sure and watch the video on post #8. Link to comment Share on other sites More sharing options...
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