kiahn Posted August 30, 2009 Report Posted August 30, 2009 hey all I'm not brilliant at mechanical fault finding so here is the problem 4age from an ae86 (RWD manifold) just dropped into a ke70 and it is doing something wierd, if we unplug the injectors the engine doesnt change revs much (maybe 50rpm max) the idle is alright and at correct rpm, the TPS is set correct and there is plenty of fuel as you can smell its over fueling and see it on plugs too when you goto rev it the timing changes so much that it doesnt want to climb revs fast, gets up to temp like normal and stays there we suspect the oxy sensor is to blame but we don't to what degree it effects the performance (obviously mixture is effected but to what extent) please help as I'm starting to get frustrated and run out of ideas cheers Quote
Evan G Posted August 30, 2009 Report Posted August 30, 2009 hey all I'm not brilliant at mechanical fault finding so here is the problem 4age from an ae86 (RWD manifold) just dropped into a ke70 and it is doing something wierd, if we unplug the injectors the engine doesnt change revs much (maybe 50rpm max) the idle is alright and at correct rpm, the TPS is set correct and there is plenty of fuel as you can smell its over fueling and see it on plugs too when you goto rev it the timing changes so much that it doesnt want to climb revs fast, gets up to temp like normal and stays there we suspect the oxy sensor is to blame but we don't to what degree it effects the performance (obviously mixture is effected but to what extent) please help as I'm starting to get frustrated and run out of ideas cheers yea i reckon o2 sensor, there surpose to be some vacuum/mechanical advanced when accelatrating, a bloke at tafe got a 400kw r33 godzilla and it and it advances 45 degrees at idle Quote
kiahn Posted August 30, 2009 Author Report Posted August 30, 2009 oxy sensor is only at cruise though, it leans it out for fuel economy, i have a map sensor and electronic ignition both are working, it advances good when it revs Quote
Evan G Posted August 30, 2009 Report Posted August 30, 2009 oxy sensor is only at cruise though, it leans it out for fuel economy, i have a map sensor and electronic ignition both are working, it advances good when it revs you ecu is probally getting a impluasbly signal from the o2 and running in safe mode, Quote
kiahn Posted August 30, 2009 Author Report Posted August 30, 2009 done cu diagnostic test now and it says the Throttle position sensor and the air intake temp sensor are to blame does this sound right? Quote
Evan G Posted August 30, 2009 Report Posted August 30, 2009 done cu diagnostic test now and it says the Throttle position sensor and the air intake temp sensor are to blamedoes this sound right? if you got faults for them replace em both and erase the ecu of any faults codes after replacing the parts :lol: Quote
flat out Posted August 30, 2009 Report Posted August 30, 2009 yeah it does, my 4age was never run with an 02 sensor and went fine so i have been told and have personally seen Quote
Roo Posted August 30, 2009 Report Posted August 30, 2009 so you unplug the injectors? and the car still runs? wtf did you set your timing with a timing light? Quote
irokin Posted August 30, 2009 Report Posted August 30, 2009 so you unplug the injectors? and the car still runs? wtf I think he means individually. Its not abnormal for a car to continue running normally with an injector unplugged. The cylinder thats missing the injector just gathers fuel from the other manifold runners and still fires fine, especially if its a batch fire ECU. Quote
kiahn Posted August 30, 2009 Author Report Posted August 30, 2009 oh ok irokin you sounds correct, stupid early version of EFI so all i have to do is fix the problems then erase them from the ecu? Quote
LittleRedSpirit Posted August 30, 2009 Report Posted August 30, 2009 oh ok irokin you sounds correct, stupid early version of EFI so all i have to do is fix the problems then erase them from the ecu? Replace what it tells you to be broken. Quote
kiahn Posted August 30, 2009 Author Report Posted August 30, 2009 will do :lol: dads gonna check through his wiring during the week and make sure its ok Quote
kiahn Posted September 5, 2009 Author Report Posted September 5, 2009 alright update: wiring fixed idle perfect and revs fine timing is good but when you go to rev it it dies first then builds up as if there is a delay in the map sensor or something. the vaccum hose to the map sensor is about triple the normal length, would this cause it? Quote
flat out Posted September 5, 2009 Report Posted September 5, 2009 can you possibly shorten it and try that? how do you tell the fault codes? would be handy to know (new to 4age's and efi) Quote
Roo Posted September 6, 2009 Report Posted September 6, 2009 can you possibly shorten it and try that? how do you tell the fault codes? would be handy to know (new to 4age's and efi) club4ag.com its in there reference section Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.