sparkysx

iTrader: (2)

I'll get contacting people soon, not really driving the car this week so no worries, got the next 2 weeks off though so will get it looked at then.

sparkysx

iTrader: (2)

Sorted it!

It wasnt an electrical problem and it wasnt the MAF sensor or anything else like that. For some reason the idiot who owned the car before me decided to remove the bump stop for the accelerator pedal, causing the ECU to read about 110% throttle when I put my foot flat to the floor, and therefore putting it into limp home mode, why it didnt throw a cel I dont know, but that was the problem. Now I just need to buy a bump stop from somewhere, ebay or main dealer I think.

dynamix

iTrader: (3)

got one here mate - taken it off my car.

I love 110% throttle

Splitpin

Theory says it should have. Anything sufficient to cause limp mode should have illuminated the CEL. Although it is also presumably possible that the removal of the end stop was sufficient to knock the ECU throttle angle calculation out of whack without the throttle sensor voltage itself being sufficiently out of spec to trigger the trouble code.

Anyone with the ability to look at the diagnostic data would have been able to tell you exactly what was going on - although it's a moot point now if you're confident that the problem is fixed.

There's an obvious question though: Does your check engine light come on when you turn the ignition on (and go out after starting the engine)? If you don't see it come on at all, then the bulb has either failed or been removed by the previous owner.

ZEN Performance

But the throttle stop is not on the pedal, it's on the throttle body, sounds odd to me that it should be fixed by this.

sparkysx

iTrader: (2)

I spoke way to soon, I bodged something up to act as a stop and took the car out and its still doing the problem!!!!!!! The cel light does work as its supposed to. I'm now wondering if its buggered the throttle position sensor?

sparkysx

iTrader: (2)

Really annoyed now, I thought it was sorted

Splitpin

It is most unlikely that simply removing the rubber bumper would break an otherwise good throttle position pot. As Paul says there is an additional physical limit stop on the throttle body itself that should prevent over-rotation of the quadrant (and therefore the pot).

As things stand it sounds likely that the problem your car is suffering is absolutely nothing to do with the removal of the pedal bumper. The next best move you could make is probably to get your car examined by someone capable of reading the diagnostic stream as this will remove a significant chunk of the guesswork and assumption under which you are currently labouring.

From what you've said so far, you don't see the check engine light when the boost pressure is limited. As such, it seems unlikely that the ECU is disabling boost (i.e. instigating limp mode) as under these circumstances you would expect to see the CEL.

As such, it seems possible, from what we know at this point, that it isn't actually limp mode at all, but some physical problem with the turbo or pressure control system - clogged boost pipework or sticking wastegate for example.

It is also highly unlikely to be a "dry joint" in the ECU. As has already been said, the manufacturing processes make this sort of problem very rare nowadays. In addition, if there was an issue of this sort in play, again it is highly likely that you would be seeing the CEL, whether for a faulty sensor, or the boost control solenoid circuit.

If you get the car diagnosed it'll be pretty obvious straightaway what is (or isn't) happening. If the wastegate solenoid duty is responding normally, for example, that rules out any sort of boost limiting in the ECU and implies that the problem is rooted under the bonnet. If on the other hand it's caused by a sensor misread, whether throttle position or elsewhere, it'll be obvious from looking at the real time data, if not the trouble code memory.

dynamix

iTrader: (3)

If the ecu is seeing det, it can/will adjust the advance multiplier and if it reduces this to a sufficient level it will put it into limp mode. It will do all of this without flashing the CEL light.

sparkysx

iTrader: (2)

I really really appreciate the good advice, i'm gonna have to accept that I cant diagnose this myself and take it to a specialist, most of whom will have seen problems like this many times before.

Thanks again.

Keith Collings

iTrader: (3)

FWIW - I am having the same problem on my MY03 WRX. I have a post on 22B about this and the consensus is to get expert advice.

I've used ECUExplorer to trouble shoot the problem, If I reset the ECU, I get normal boost for a short while (read a minute or so) then it drops back from around 14 psi to 7 psi. The key to the issue seems to be that the Ignition Advance Multiplier is getting knocked back from around 14 to as low as 2. This, the experts tell me, is due possibly to the ECU detecting knock. I have a standard build (no decats etc) and have run on V-Power without solving the problem.

I've given up trying to solve it myself and have the car booked into David at APi on October 2nd to look at this issue when he does MOT work and a major 100k service.

sparkysx

iTrader: (2)

I dont really know anything about "knock" i've heard of it of course but dunno what it is, or how serious it is, or how to get rid of it.

Keith Collings

iTrader: (3)

Knock is not good I'm not sure that it is really my problem - but I think it needs an expert to sort it out. So it's booked into one !

sparkysx

iTrader: (2)

Whoever of us gets the answer first, please come back here to report it.

Keith Collings

iTrader: (3)

I should know something by October 9th when I collect the car - will let you know

sparkysx

iTrader: (2)

They are having it for a week?

sparkysx

iTrader: (2)

P.S, you have the same surname as me, with the "g" aswell!

Keith Collings

iTrader: (3)

Yep - Sat to Sat - about 3 days work but I have trouble getting there during the week - bloody work

sparkysx

iTrader: (2)

It doesnt do this problem unless I let it hit peak boost a lot, if I limit it to say 12.5 psi or less, it doesnt do it.

sparkysx

iTrader: (2)

With the exception of the Prodrive backbox, the car is now standard.

sparkysx

iTrader: (2)

Booked in with Alan Jeffery on the October 1st, so should be sorted then. After that i'm selling it and buying an saloon. Bought a wagon intending on using it for work, but shower doors wont fit inside this. Still, doesnt seem like there are many blobeye wagons on PH atm, so should sell quick.

rookymatt

iTrader: (15)

You'll definately sell it mate. As far as i can see, there is quite alot of demand for blob station wagons. However i was lead to believe it was the sti versions that are the very very saught after ones.

sparkysx

iTrader: (2)

Yeah I know the STI's are sought after, but they are rare as rocking horse s**t