I posted a thread about my problem on the 3rd gen spec. forum but didn't get any answers. Anyway Im a new owner of a modded FD, intake, DP, catback, fuel pump, streetport, fuel pump 1300cc secondaries, and power FC. Anyway my first few days with the car went well and it was making tons of power even though it wasnt tuned properly. Then a few days ago I was riding down the road and it started backfiring and stuttering. I turned it off and let it rest and since then it hasn't really ran quite like it did originally. That is for instance in 1st gear unless I go WOT it makes no boost, and in the the rest of the gears it makes boost but it is jumpy and still backfires from time to time. My boost will also occcasionally spike to 12 psi and hold though its programed to only go 10. My guess is that I'm running rich and need a tune... but I'm a little afraid bc I don't know the car very well yet. Also can someone give me the # of a place in GA I could get it tuned? Thanks!

Justin

 

well, i totally agree that you should get the car tuned. check the Regional Forum for a tuner in Georgia.

as for your problem, it's hard to say without more info or driving the car myself - but i would definitely advise you to keep it simple at first. knowing how the Gen III's are notorious for vacuum hose failures, that would be my first guess to your problem.

try running a search in the Gen III forum for vacuum hose problems. start there ... if it turns out that that's not it, then come back and see if we can get you some more help.

 

Have the wastegate and Blow-off valve checked. These are most likely your problems. Check you boost sensor. You say that the car is programmed to only go to 10psi; I assume you have an aftermarket boost controller. Make certain it (the boost controller) is working properly and is hooked-up correctly.

No boost at low acceleration is a broad term. If you mean under 1/4 throttle, then you'll probably not make much above atmospheric anyways. Turbos "spool" up under load. That's why you won't get a boost reading if you rev it while in neutral (unless you have lag countermeasures). If you mean at 7/16+ throttle, then you probably have a sticky Blow-off valve or wastegate. That, or maybe the boost controller is malfunctioning (bad connection[s]).

Hey, if you're totally stumped, get a multimeter (digital type) and test ALL the electronics according to the specifications in a shop manual. If everything tests okay, then check what could directly be related to the problem (read: keep it simple). Get a schematic of how the PFC is supposed to be conencted and check all the leads. Also, if it appears to have the factory vacuum hoses, REPLACE THEM. Especially the ones near the turbo/exhaust manifold. Just go through everything piece-by-piece and eventually you'll find the answers you're looking for.

Boost spike can be caused by the addition of a downpipe and other mods. Usually translates into the wastegate not being able to operate quickly/efficiently enough for the velocity/volume of exhaust gasses.

It's an induction-related problem, so check all the intake stuff, turbo included. Probably not the answer you're looking for, but it does work.