Golfpro Posted November 18, 2008 Share Posted November 18, 2008 The car has been driving brilliantly since the rebuild 9 months ago (PHR street kit, PHR stage1 fuel system, MAP ECU2 etc). In the last couple of days it has suddenly gone mad. The AFRs seem to be reacting in slow motion. When accelerating normally the AFRs go lean (18) for a couple of seconds then gradually rise to normal at 14.5. When lifting off they fall to 10 or 11 as expected but take ages (10 seconds) to slowly rise back up to 14.5. I was thinking fuel pump or FPR trouble rather than mapping as the fuelling was perfect until recently. Does anyone have any ideas before we have to take things apart? Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 Have you checked all the vacum pipes are in good condition and are not split around the map sensor or a T piece broken;) Quote Link to comment Share on other sites More sharing options...
Golfpro Posted November 18, 2008 Author Share Posted November 18, 2008 I have checked all the ones I can see. It is kinda difficult these nights as it is pitch black bu the time I get home. Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 I have checked all the ones I can see. It is kinda difficult these nights as it is pitch black bu the time I get home. Lol yes it is but if it is one of them it should make the car smoke black smoke on tick over:) Quote Link to comment Share on other sites More sharing options...
Golfpro Posted November 18, 2008 Author Share Posted November 18, 2008 Which vac lines in particular do you think would cause the AFRs to suddenly behave so strangely? Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted November 18, 2008 Share Posted November 18, 2008 I would be inclined to check the TPS, as this can cause some odd behaviour when out of adjustment. Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 Any near the map sensor on the intake manifold mine was missing the other week evertime i put my foot down the afr went straight around to lean and then let off it was ok only to find that one of the T pieces on the vacum pipes had split;) Quote Link to comment Share on other sites More sharing options...
Golfpro Posted November 18, 2008 Author Share Posted November 18, 2008 Lol yes it is but if it is one of them it should make the car smoke black smoke on tick over:) Checked the exhaust gasses and they are grey/white. No split vac hoses as far as I can see. Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 Is it only under boost or steady driving affecting it aswell Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 What fuel pressure are you running under load should be around 3 bar Quote Link to comment Share on other sites More sharing options...
Golfpro Posted November 18, 2008 Author Share Posted November 18, 2008 Is it only under boost or steady driving affecting it aswell It happens even when accelerating slowly. It only levels once cruising speed is acheived. Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 Have you you checked all the clips are on correctly on the injector's Quote Link to comment Share on other sites More sharing options...
Golfpro Posted November 18, 2008 Author Share Posted November 18, 2008 Have you you checked all the clips are on correctly on the injector's Dont really went to start taking things apart until I have an idea of what the problem might be. Not sure what the fuel pressure is under load but at idle it is 25psi. Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 Mine is 2 bar on tickover which is 29psi and under load it is 3 bar which is 43psi to check under load there should be a vacum pipe on the fpr kink it over to stop the flow of air to the fpr and it should go up to around 3 bar ish;) Quote Link to comment Share on other sites More sharing options...
Golfpro Posted November 18, 2008 Author Share Posted November 18, 2008 Mine is 2 bar on tickover which is 29psi and under load it is 3 bar which is 43psi to check under load there should be a vacum pipe on the fpr kink it over to stop the flow of air to the fpr and it should go up to around 3 bar ish;) FPR reading went up to about 32 when I pinched the pipe. Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 Other than this it might be a clogged fuel filter someone on here will have alot more knowledge about this fella Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 Do you know what the condition of the fuel filter is like has it been changed with the upgrade Quote Link to comment Share on other sites More sharing options...
Golfpro Posted November 18, 2008 Author Share Posted November 18, 2008 Do you know what the condition of the fuel filter is like has it been changed with the upgrade The entire fuel system is new (PHR stage 1). Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 What about the afr sensor was this new? Quote Link to comment Share on other sites More sharing options...
Golfpro Posted November 18, 2008 Author Share Posted November 18, 2008 What about the afr sensor was this new? Yes. Brand new Innovative Motorsports G3 kit. Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 Other than testing the injectors i can not help anymore fella tryed everything i could sorry fella hope you sort this out! Just check all the clips are down on the top of the injectors and are not loose:( Quote Link to comment Share on other sites More sharing options...
Golfpro Posted November 18, 2008 Author Share Posted November 18, 2008 Other than testing the injectors i can not help anymore fella tryed everything i could sorry fella hope you sort this out! Just check all the clips are down on the top of the injectors and are not loose:( Will keep looking. Cheers Bud. Quote Link to comment Share on other sites More sharing options...
j80leo Posted November 18, 2008 Share Posted November 18, 2008 No worries at all fella Quote Link to comment Share on other sites More sharing options...
Guest pitstopralph Posted November 18, 2008 Share Posted November 18, 2008 I've no real experiance with the set up you are using but from a diagnostic point of view, You need to establish whether the car is reacting strangely or just the AFR gauge. The quickest way to tell is to get in onto a four gas with someone who knows how to read it. It sounds to me as though the lambda sensor for the gauge is lazy. Quote Link to comment Share on other sites More sharing options...
Dazzi Posted November 19, 2008 Share Posted November 19, 2008 Have you got good grounding to the gauge? Quote Link to comment Share on other sites More sharing options...
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