Indiana Posted May 7, 2011 Report Share Posted May 7, 2011 Then why does my diagram on the bottom of my hood show one, and why is there one hanging on my firewall just above the master cylender? It is also listed in the '86 FSM as one input to the ECU. Or am I just completely retarded?Geez that's an obvious mistake on my part not reading that again. That is all pre87s have a pressure sensor. This sensor is to compare boost pressure to atmospheric every few minutes. The sensor in the MAF can't measure boost pressure because boost isn't ever in there. Link to comment Share on other sites More sharing options...
Indiana Posted May 7, 2011 Report Share Posted May 7, 2011 Now I don't remember if you are using two OEM injectors that have H or J on them or if anyone has asked. Did you have them cleaned or not? Link to comment Share on other sites More sharing options...
DarksideDSM Posted May 7, 2011 Author Report Share Posted May 7, 2011 I havent had them cleaned and they have a symbol it looks like then J then 3-4 numbers starting with a 3. Its hard to see and Its on the side just under the plug. I put the maft on the car and Im having the same problem as stallion. I put it on and although it changes how it starts when I mess with the dials, It still runs rough and dies. I think though that maybe the wrong plugs mixed with the fact that they are probably fouled from the starting all the time for troubleshooting and the gap at .038 may be the reason. Im going to pull the plugs, clean them, regap to .032 or so and test my map. and im going to put in my widebnd. after that, If it doesnt start to run good im ordering new injectors I guess. Link to comment Share on other sites More sharing options...
StarquestRescue Posted May 7, 2011 Report Share Posted May 7, 2011 (edited) So the problem must be with the map sensor. The voltage went unchanged even when boosting, the issue is progressing as the car doesn't even want to stay running any longer. Anything else to check or do I just need to buy another sensor?Now go to the sensor end of the harness find the same yellow wire, and see if you have continuity from there to the ecu. Also bypass your make shift solenoid set up, and run the pressure / vacuum line directly to the pressure sensor and see if you get a different voltage reading. What voltage were you getting in the yellow wire. Edited May 7, 2011 by StarquestRescue Link to comment Share on other sites More sharing options...
Indiana Posted May 7, 2011 Report Share Posted May 7, 2011 You are really just wasting your time until you have those cleaned. Those injectors spray lots of fuel and when dirty are inconsistent. When they are dirty they spray so bad that if you had everything else for the engine brand new and perfect they would foul plugs just trying to get it to start. Link to comment Share on other sites More sharing options...
StallionProject86 Posted May 7, 2011 Report Share Posted May 7, 2011 Now go to the sensor end of the harness find the same yellow wire, and see if you have continuity from there to the ecu. Also bypass your make shift solenoid set up, and run the pressure / vacuum line directly to the pressure sensor and see if you get a different voltage reading. What voltage were you getting in the yellow wire. Alright good idea, which of the three lines do I run into the sensor? The one that was from the air canister? And voltage stayed @2.8 Link to comment Share on other sites More sharing options...
StarquestRescue Posted May 7, 2011 Report Share Posted May 7, 2011 Alright good idea, which of the three lines do I run into the sensor? The one that was from the air canister? And voltage stayed @2.8The one form the intake manifold. Link to comment Share on other sites More sharing options...
DarksideDSM Posted May 7, 2011 Author Report Share Posted May 7, 2011 Ok, so I checked the plugs and they arent fouled. They look brand new. I did reduce the gap a little. The map sensor is working within the factory specs measured at the ecu. So now Im going to put the wideband on and try and tune not blind. I am pretty sure I agreee with indiana though and need to clean my injectors or replace them. I will take them out today and try and clean them according to the sos manual. If that fixes it for now then I will drive it like that but only till I can get new ones. Link to comment Share on other sites More sharing options...
Indiana Posted May 7, 2011 Report Share Posted May 7, 2011 If the MAP was bad it could be lean and your plugs would show that but you may have been tuning that out with the translator. I'd clean those injectors it won't hurt anything. Link to comment Share on other sites More sharing options...
StallionProject86 Posted May 8, 2011 Report Share Posted May 8, 2011 (edited) StallionProject86, on 07 May 2011 - 12:39 PM, said: Alright good idea, which of the three lines do I run into the sensor? The one that was from the air canister? And voltage stayed @2.8StarquestRescue, on 07 May 2011 - 09:58 AM, said: The one form the intake manifold. So I just got through doing this and it didn't change. I also checked the plug side (in the engine bay on the firewall) and the reading is the same as from the ecu. . Edited May 8, 2011 by StallionProject86 Link to comment Share on other sites More sharing options...
DarksideDSM Posted May 8, 2011 Author Report Share Posted May 8, 2011 I cleaned the injectors, put in my wideband, and put some more gas in the tank cause it was low. It started! It ran rich still, about 13-12.5. and it ran about 1800 rpms. I did a tps isc reset again. I got the rpm's down to right. now it runs but like it has no mas. rich and skips then revs when you hit the throttle. The maft also has the green led on like its in mid and nothing will change the afr. Its like the adjustments dont work. and if i unplug the gm maf it does nothing, no change. Now what do I do? how do I check the gm maff to tell if its good. I assume it is cause the maft is not throwing a code. maybe the maft is not working correctly. should I contact the company? Link to comment Share on other sites More sharing options...
StarquestRescue Posted May 8, 2011 Report Share Posted May 8, 2011 So I just got through doing this and it didn't change. I also checked the plug side (in the engine bay on the firewall) and the reading is the same as from the ecu. .Try another sensor. Link to comment Share on other sites More sharing options...
Indiana Posted May 8, 2011 Report Share Posted May 8, 2011 Use a heated so that the ECU goes into closed loop and your MAFT will be better able to adjust for idle rpms. At idle the ECU expected a certain fuel volume and pressure with the OEM injector size and correct engine vacuum from the cam/valve train. Your MAFT only has so many settings so forget the idle one and get a heated 02 so you have more options. Link to comment Share on other sites More sharing options...
DarksideDSM Posted May 8, 2011 Author Report Share Posted May 8, 2011 (edited) Important update. I got it right so far. I still have to figure out the fine tune tomorrow. I found out that the wiring for the '86 i found on the 'great maft tuning thread' was wrong. It said black/black, red/pink, green/green, and white/gray. I dug deeper and found that It should be black/black, red/pink, and white from ecu to green from maft. according to the car wiring diagram, the white is the signal for the ecu and the green is jumped from the ground through a resistor to aproximate temp before the intake. The maft output wire is the green and grey is baro. So wired how its on the maft tuning thread is wrong. This may be your problem stallionproject. my complete wiring is:maft/carblack/blackpink/redgreen/whitegrey,brown,white,purple/no connection Once i figured this out I changed it and it would respond to tuning now, but, at max rich on idle it would be so lean it would be off the scale. aka more than 18:1. So i got the bright idea that i could offset it by setting the first dip switch to on so it thought it was a 3.5" maf and that worked. now i have it idleing at 14.3-14.7. but now when I hit the throttle it leans and skips then returns to normal. and if I hold the throttle open a little it leans to 17. so i need to tune more tomorrow but IT WORKS! Finally. Edited May 8, 2011 by DarksideDSM Link to comment Share on other sites More sharing options...
StallionProject86 Posted May 8, 2011 Report Share Posted May 8, 2011 (edited) /\ nice find I'll check that out when I get off of work. Although you said your map voltage reading is to factory specifications mine on the other hand is completely off. .but I will check. Edited May 8, 2011 by StallionProject86 Link to comment Share on other sites More sharing options...
DarksideDSM Posted May 8, 2011 Author Report Share Posted May 8, 2011 /\ nice find I'll check that out when I get off of work. Although you said your map voltage reading is to factory specifications mine on the other hand is completely off. .but I will check.You are correct about the map sensor, you have a problem with it. On the other hand, what I was saying to you is strictly the wiring. I forgot you were having the map problem. I wish you good luck with that. Link to comment Share on other sites More sharing options...
StarquestRescue Posted May 8, 2011 Report Share Posted May 8, 2011 maft/carblack/blackpink/redgreen/whitegrey,brown,white,purple/no connection I come up with.Maft----Car---------------Functionblack---black--------------Groundpink----red----------------Powergreen---white/black stripe-frequencybrown---green-red stripe---air tempgray----no connection------barowhite---no connection------rpmpurple--no connection The wiring to the temp sensor in the over the valve cover pipe should not be messed with in my opinion. Link to comment Share on other sites More sharing options...
DarksideDSM Posted May 8, 2011 Author Report Share Posted May 8, 2011 I come up with.Maft----Car---------------Functionblack---black--------------Groundpink----red----------------Powergreen---white/black stripe-frequencybrown---green-red stripe---air tempgray----no connection------barowhite---no connection------rpmpurple--no connection The wiring to the temp sensor in the over the valve cover pipe should not be messed with in my opinion.yes. That is what I found. I also found that the afr was more stable If I have the gray baro wire hooked to the green/red temp wire on the car. The thing doesnt work though on the correct dip switch settings. I have to set it like Im using a 'super maf'. These are my settings: dips: 1on,2on,3off,4offaux 0base 0 idle 4mid 4 wot 0 Keep in mind that Im at 7500 ft elevation. My new connections are:maft/ carblack/blackpink/redgreen/whitegrey/greenpurple and white NC. and brown to green/red on ovcp Link to comment Share on other sites More sharing options...
DarksideDSM Posted May 8, 2011 Author Report Share Posted May 8, 2011 Dont be an idiot! I was. I didnt listen when I was told to not only clean my injectors but also to sand and clean the connections. I did clean my injectors just didnt think it would help, It did. then after i got the car running i moved my injector clips and it no longer started. thats when I realized that everyone was right. Clean the connections! I took it a step further. I sanded, cleaned, then applied a thin amount of solder to the male pins. Not only did it start easier but it also ran so much smoother and kept a more steady afr. Sorry to all that told me and i didnt listen. Link to comment Share on other sites More sharing options...
StallionProject86 Posted May 11, 2011 Report Share Posted May 11, 2011 (edited) So I'm still in the pits, I changed the MAP sensor (boost sensor) and my car is in the same condition. .this has been a terribly frustrating month. Anyway to check out the ecu? I have no clue on what else it could be. . I changed the CTS, boost sensor, pressure sensor (x2), injectors and added clips, spark plugs, cap and rotor, MAF, fuel filter, fuel regulator, and did the TPS/ISC reset (x2) When I go to start it she wants to warm up but then drops down and dies almost instantly. .I've tried to give it gas but that cuts off the engine even sooner. ??? Edited May 11, 2011 by StallionProject86 Link to comment Share on other sites More sharing options...
The Rabbit1 Posted May 11, 2011 Report Share Posted May 11, 2011 haw are your wires coming off the plug on the cts? does your isc zip smoothly or does it kind of move in steps? Link to comment Share on other sites More sharing options...
StallionProject86 Posted May 12, 2011 Report Share Posted May 12, 2011 haw are your wires coming off the plug on the cts? does your isc zip smoothly or does it kind of move in steps? Well their connected like they were stock. Black wire in the rear and the other one in front of it (as if you looked down on it from the drivers side) and yes the isc flowed smoothly. Link to comment Share on other sites More sharing options...
StallionProject86 Posted May 12, 2011 Report Share Posted May 12, 2011 Also a little update. .my brother got the car to at least idle. .still back firing issues persist when it enters boost. Sound like a vacuum leak? I can't here where its coming from at all though if there is in fact a leak..and one other thing the MAF translators green led light stays on but appears to be dim, stating that the car is cruising right? Which is not the case this is all being carried out in neutral and running @idle. Don't know if it means anything but thought I would list it. Link to comment Share on other sites More sharing options...
The Rabbit1 Posted May 12, 2011 Report Share Posted May 12, 2011 use a mighty vac, the slightest leak will cause it to run rich and/or backfire. You can't hear a small leak, only big ones. Link to comment Share on other sites More sharing options...
StallionProject86 Posted May 12, 2011 Report Share Posted May 12, 2011 I think my ecu is toast. .I bought another boost sensor installed it and no change as mentioned above, I checked the readings from the plug (ecu to sensor) and I still have the readings of 2.5-2.6 that is half of what I was told it should be at what does that mean. ? Link to comment Share on other sites More sharing options...
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