15 replies to this topic

[JDM_FOZZY]

Hey guys I was having a small issue of when I got to higher boost it would hesitate a bit so I booked it into a shop so it could get fixed. It came back 3000x worse. It idles like complete crap, absolutely chews fuel and bogs down a hell of a lot when driving. The shop reckoned it was the map sensor but I've replaced it twice even tried a mates one that came straight out of his car and still didn't fix the problem. They also moved a heap of the vacuum hoses around which I have moved back to how they were in the first place. I haven't driven my car for 3 weeks because of this issue. (current financial state can't have another shop look at it) I'm over it. I took it back the same day to the shop but they reckon it was like that when they got it. Which is complete bull5h!7. I've checked for air intake leaks and couldn't find any without using a air compressor as I don't have one. It is throwing the MAP code but the MAP itself definitely isn't the problem. Can anyone tell me which wire on the map sensor does what so I can try trace them back to check for breaks. I have a multimeter so I can test for voltage. Any help AT ALL will be greatly appreciated. 

[JDM_FOZZY]

Here's a video of the idle. 

[duncanm]

MAF ok?

[JDM_FOZZY]

Just tested both MAF and MAP. Both have 5V supply and both have 1.30V on the signal wire and it increases with revs. 

[duncanm]

AFAIK (and I may be wrong here) - MAP isn't used for much apart from sampling atmospheric at turn-on, and detecting overboost for boost cut. 

 

Can't see it causing idle issues.

 

Unstable idle could definitely be a manifold (post-throttle body) leak - would also cause overfuelling on boost due to boost leak.

 

Try spraying some WD40 or carb cleaner around suspect points while idling and see if it clears up the idle.

[JDM_FOZZY]

Tried it. Didn't change anything.

[Bumpty]

 Nobody knows.jpg   127.89KB   5 downloads

Could it be the IACV in the wrong position/noitisop?

[El_Freddo]

Is this one of the foresters with that butterfly system in the intake manifold above the heads to improve low down torque and top end performance?

A mate of mine had one and it caused loads of issues. I'm 99% sure they got rid of the butterflies but kept the actuator motor to keep the ECU happy. Worked a treat.

Dunno if that'd help you out though.

Cheers

Bennie

[Jimbo]

Nah too early a model for that black magic, Bennie!

Thought about a leaky injector or a dud coil pack?

[jonesyGT]

Sounds like an air leak.
Hey a can of wd40 with the long skinny needle & spray around & along top & bottom of air intake. Listen for changes. If that does nothing, start on vacuum lines.

[andrew_k]

+1 to air leak theory.

Cleaned your IACV and IACV sensor to take it out of the equation?

Are the codes cleared? Sounds like you're in limp mode. Also check your rear O2 sensor is at the right voltages

[JDM_FOZZY]

Will it stay in limp mode if I fix the problem but not clear the codes? 

[duncanm]

reset the ECU (disconnect battery for half an hour) -- this'll clear the codes and take it out of limp till the problem that triggered it occurs again (** if it is in limp, that is).

[andrew_k]

If you don't want to wait half an hour you can hold the brake for 10 seconds instead

[JDM_FOZZY]

Took it to a mate with a workshop in town. He put it straight in, checked it out. Thought maybe fuel pump is clogged up so pulled that out put a new bag on the bottom of it, all for free, it's good to know people. Still didn't fix it. It's not throwing any codes anymore but still running sh7t. He said to check the fuel hoses around the fuel filter so I'll check them next. As when he pinched the fuel hoses, 1 made the car stall where as the other didn't. Should they both stall? 

[JDM_FOZZY]

Another update, found a slight boost leak and fixed that but didn't change anything. Changed fuel pump, if anything it made it worse. Looks like the intake mani is coming off to do injectors.