FijiPhil Posted January 13, 2011 Report Share Posted January 13, 2011 My 88 Tsi is giving me an awful lot of lip! Lol. This motor was recentltly transplanted from another 88 quest and ran pretty well when it was in that car. My wideband reads between 10.4 and 10.0 at idle. If you give it gas it spikes way lean. I put a set of known good 650cc and 950cc injectors on it and there was no change. What else should I be looking at? Im guessing it would be a sensor issue somewhere but im not sure where to check. Its more or less stock, the vacuum lines and emissions have been eliminated, it has an 18g, and a blow off valve. Thanks! Link to comment Share on other sites More sharing options...
The Rabbit1 Posted January 13, 2011 Report Share Posted January 13, 2011 how fast does it spike? sounds like you have vacuum leak. Link to comment Share on other sites More sharing options...
nycain Posted January 13, 2011 Report Share Posted January 13, 2011 HEY GUYS I'M EXPERIENCING THE SAME PROBLEM WITH MY QUEST,MY CAR HAS 135XX MILES NO MODS STOCK , I HAVE A FUEL PRESSURE GAUGE THAT READS 38 PSI AT IDLE ADD A LITTLE REV GOES UP TO 39-40 PSI MY VACCUM IS OK NO LEAKS AT IDLE IT READS 20 ON MY BOOST GAUGE , IN DRIVE IS A LITTLE UNDER 10 , I CHANGED THE MAF SAME PROBLEM, CLEAN GROUNDS WHEN I REV THE CAR IT BAFFLES , REMOVE THE SECONDARY INJECTOR SAME PROBLEM , REV THE CAR UP TO 2500 RPM UNPLUG THE PRIMARY REVS OUT , PLUG IT BACK IN REV IT OUT UNPLUG THE SECONDARY IT BAFFLES REAL BAD , I HAVE 4 OTHER PRIMARY INJECTOR SAME ISSUES NEED HELP Link to comment Share on other sites More sharing options...
FijiPhil Posted January 13, 2011 Author Report Share Posted January 13, 2011 how fast does it spike? sounds like you have vacuum leak. Light throttle will lean out to maybe 13 or 14. If you give it heavy throttle it will spike to 17 or just read --- and go all the way red. A vacuum leak isnt impossibe.. but Im not sure where it could be. Almost all the vacuum ports have been eliminated and plugged. I can go over it to make sure I didnt miss a plug somewhere but more or less all I have is vacuum for my BOV, boost gauge, and vac advance. The BOV is a real turbo XS and seems to be functioning properly. Link to comment Share on other sites More sharing options...
The Rabbit1 Posted January 13, 2011 Report Share Posted January 13, 2011 Is the bov closing properly? does your vacuum advance hold vacuum? Link to comment Share on other sites More sharing options...
FijiPhil Posted January 13, 2011 Author Report Share Posted January 13, 2011 Is the bov closing properly? does your vacuum advance hold vacuum? Yes the BOV appears to be closing properly. Ill double check the vac advance. Ive had bad ones in the past. but they only gave me trouble under full boost. Link to comment Share on other sites More sharing options...
Wolf87Conquest Posted January 13, 2011 Report Share Posted January 13, 2011 When was the last time you changed the oxy sensor? This sensor is the main one the ECU uses to determine injector on time. Are you sure the injectors are not sticking open or leaking? The injector wires should have 12 volts to one side all the time (key on) but the other wire should not have ground (key off). The ground is provided by the ECU to fire the injectors...test it. If your injector wire has a ground with key off, then you'll need to trace it out and find where it's getting ground and repair it. Use solder and shrink wrap for automotive wire repairs. Crimp connectors would be a second choise. Link to comment Share on other sites More sharing options...
FijiPhil Posted January 14, 2011 Author Report Share Posted January 14, 2011 When was the last time you changed the oxy sensor? This sensor is the main one the ECU uses to determine injector on time. Are you sure the injectors are not sticking open or leaking? The injector wires should have 12 volts to one side all the time (key on) but the other wire should not have ground (key off). The ground is provided by the ECU to fire the injectors...test it. If your injector wire has a ground with key off, then you'll need to trace it out and find where it's getting ground and repair it. Use solder and shrink wrap for automotive wire repairs. Crimp connectors would be a second choise. Its a newer bosch universal that i used on another car recently with good results. I dont believe the injectors are having issues, as i mentioned the injectors have less than 1,000 miles, and the car starts on the second or third crank. I thought that a leaky injector would cause it to crank longer than that on start up. Ok, I can look into that. I guess I should mention it has a set of new injector clips soldered on also. Link to comment Share on other sites More sharing options...
Starfighterpilot Posted January 14, 2011 Report Share Posted January 14, 2011 (edited) Light throttle will lean out to maybe 13 or 14. If you give it heavy throttle it will spike to 17 or just read --- and go all the way red. A vacuum leak isnt impossibe.. but Im not sure where it could be. Almost all the vacuum ports have been eliminated and plugged. I can go over it to make sure I didnt miss a plug somewhere but more or less all I have is vacuum for my BOV, boost gauge, and vac advance. The BOV is a real turbo XS and seems to be functioning properly. There is one more vacuum system that you didn't mention - the vacuum metal tubing/hoses going to the brake booster and the rest of the system. The hose coming off of the intake manifold fitting going to the tee where the tubing splits gets crusty and brittle with age and has been known to split or crack cuz of engine heat over time. Check that hose and the others in that vacuum system (see FSM 5-43 for that system layout). I'd also check all of the intercooler and the turbo intake accordian hose hose joints for connector tightness & hose splits. Also especially check underneath the connector hose between the OVCP metal tube and the TB - the only good way to check this hose and the accordian hose is by removing 'em and then looking at 'em. Have you checked the "rubber" tubing between the Fuel Pressure Regulator (FPR) and the TB? Pull it off and smell the inside of it. Does it stink from gas? If so, the FPR diaphram is shot and the FPR is FUBAR. Also check the tubing you pulled off the FPR for holes/cracks or crustiness. Does this "rubber" tubing fit tightly to the TB & FPR vacuum nipples? What does your fuel pressure read for various loads on the engine? If ya don't know, then ya gotta mount a nippled plug, tubing & a pressure guage in the TB top piece rear threaded plug hole; after removing that plug. Put some spacer washers under the drivers side hood hing mounting bolts to raise the hood enough to keep the hood from crimping closed the tubing and tape the guage to the windshield to read the fuel pressure in real time. Then take your Lady out for a test drive to see what the FPR/fuel pressure is doing under various loads. Check the throttle cable for the proper slack. For What It's Worth. KEN Edited January 14, 2011 by Starfighterpilot Link to comment Share on other sites More sharing options...
ConQue Posted January 16, 2011 Report Share Posted January 16, 2011 My 88 Tsi is giving me an awful lot of lip! Lol. This motor was recentltly transplanted from another 88 quest and ran pretty well when it was in that car. My wideband reads between 10.4 and 10.0 at idle. If you give it gas it spikes way lean. I put a set of known good 650cc and 950cc injectors on it and there was no change. What else should I be looking at? Im guessing it would be a sensor issue somewhere but im not sure where to check. Its more or less stock, the vacuum lines and emissions have been eliminated, it has an 18g, and a blow off valve. Thanks! Try to double check your temp sensor, that relates to computer to idle normal. Link to comment Share on other sites More sharing options...
Shelby Posted January 20, 2011 Report Share Posted January 20, 2011 any time you have a lean out condition under load ,,always test the fuel system pressure under load ,,at no time can the pressure drop , if it does it shows a restriction eather from pump to inj or more likely a suction problem with intank filters Link to comment Share on other sites More sharing options...
FijiPhil Posted January 24, 2011 Author Report Share Posted January 24, 2011 Hey guys, sorry I havent updated this in forever.. I let the car warm up, and after it gets closer to operating temps, it idles between 13.7 and 14.6. Pretty much just fluctuates between those two values. Under part throttle it seems to make ok power, and is in the 12s on the wideband. But, full throttle will make it lean out and cut out. So my thoughts are maybe a issue in the fuel system? The fuel pump has given me trouble in the past, but after banging on it a bit it seems to work ok. All the filters are new, the tank had some corrosion, but it looked ok to me. I verified this with another local quester, and he said he wouldnt be too worried about it. I think what I will do is TPS/ISC reset (havent done this, it may help my idle fluctuations on the wideband?)New fuel pump and clean tank just to be sure thats itregrease dizzy. There are no vacuum leaks I can find, ABS has been eliminated and plugged. Am I on the right track? Link to comment Share on other sites More sharing options...
Shelby Posted January 24, 2011 Report Share Posted January 24, 2011 any time you have a lean out condition under load ,,always test the fuel system pressure under load ,,at no time can the pressure drop , if it does it shows a restriction eather from pump to inj or more likely a suction problem with intank filters you miss this Link to comment Share on other sites More sharing options...
FijiPhil Posted January 24, 2011 Author Report Share Posted January 24, 2011 you miss this Shelby, that's why I was saying I should replace my pump and clean the tank just to be sure. The filers (including in tank) are all new (cleaned the inline mesh screen) Link to comment Share on other sites More sharing options...
Shelby Posted January 25, 2011 Report Share Posted January 25, 2011 no no your missing the entire point,, replaceing parts does not give you info you need to fix the car for example lets say the rubber hose from the hard line to your fuel filter is partialy plug'd it'l cause fuel starvation and no amount of changeing out pumps or any thing else will fix it,, just for info i have had to replace several of those hoses for being partialy plug'd one was 100% plug'd it may not be a fuel problem at all but only road testing and visualy watching the fuel system pressures will tell you yes or no i have seem cars run so rich the 02's stop reading properly and say lean when in fact they are super rich Link to comment Share on other sites More sharing options...
FijiPhil Posted January 25, 2011 Author Report Share Posted January 25, 2011 no no your missing the entire point,, replaceing parts does not give you info you need to fix the car for example lets say the rubber hose from the hard line to your fuel filter is partialy plug'd it'l cause fuel starvation and no amount of changeing out pumps or any thing else will fix it,, just for info i have had to replace several of those hoses for being partialy plug'd one was 100% plug'd it may not be a fuel problem at all but only road testing and visualy watching the fuel system pressures will tell you yes or no i have seem cars run so rich the 02's stop reading properly and say lean when in fact they are super rich Gotcha. Looks like I have some work to do. just curious, the car was run for a few mins with a turbo with bad oil seals. It dumped a ton of oil out of the exhaust. It dripped out from around the WB sensor (located just after the downpipe straightens out, about 18 inches from the turbo. Could that mess up the sensor and cause an inaccuate reading? Link to comment Share on other sites More sharing options...
Shelby Posted January 25, 2011 Report Share Posted January 25, 2011 http://www.starquestclub.com/forum/public/style_emoticons/default/rolleyes.gif yep odds are good that the 02 sensor is unable to read gas 02 signals Link to comment Share on other sites More sharing options...
Starfighterpilot Posted January 26, 2011 Report Share Posted January 26, 2011 Below is a source for the Mitsu OEM O2 sensor which were made by Denso. From a Mitsu dealer they are about $120.00 the last time I checked which was about 1 1/2 years ago. God only knows what they cost now. This company has 'em for $44.20 shipped. Any time I can replace a Starquest sensor with OEM rather than buying an after market one I do it even tho it costs much more. Mitsu/Denso sensors seem to last much longer than the ones made in Red China. Buying one for $44.20 shipped - it's a no brainer. http://www.discounto2sensor.com/store/?D=denso%2boxygen%2bsensor&PN=4294935243&Nty=1&Ntx=mode+matchallpartial&Ntk=Main&VN=4294967240+4294966587+4294964544+4294962066+4294966614&N=0&Dx=mode+matchallpartial&Ntt=denso%2boxygen%2bsensor&Nr=AND(category:Exhaust,universal:0) For What It's Worth. KEN Link to comment Share on other sites More sharing options...
Caliber308 Posted January 26, 2011 Report Share Posted January 26, 2011 Light throttle will lean out to maybe 13 or 14. If you give it heavy throttle it will spike to 17 or just read --- and go all the way red. A vacuum leak isnt impossibe.. but Im not sure where it could be. Almost all the vacuum ports have been eliminated and plugged. I can go over it to make sure I didnt miss a plug somewhere but more or less all I have is vacuum for my BOV, boost gauge, and vac advance. The BOV is a real turbo XS and seems to be functioning properly. Link to comment Share on other sites More sharing options...
Raider 2.6 Posted January 27, 2011 Report Share Posted January 27, 2011 On the o2 thing, I recently purchased a Denso from RockAuto for $26 shipped. It came with a new gasket and looked exactly like the one that came off, which I'm guessing was original. Has the flange on it and the wire/connector is correct, part number 2341052. Link to comment Share on other sites More sharing options...
Shelby Posted January 28, 2011 Report Share Posted January 28, 2011 On the o2 thing, I recently purchased a Denso from RockAuto for $26 shipped. It came with a new gasket and looked exactly like the one that came off, which I'm guessing was original. Has the flange on it and the wire/connector is correct, part number 2341052. it's that funny you can't find them for years then one day ,,there they are http://www.starquestclub.com/forum/public/style_emoticons/default/rolleyes.gif Raider it's good to see you again Link to comment Share on other sites More sharing options...
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