Hesitation under initial boost

Discussion and technical advice the SW20 MR2. 3S-GTE, 3S-GE, 3S-FE etc
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rossonza
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Re: Hesitation under initial boost

Post by rossonza »

SonicSW20 wrote:Did you calibrate it when you reinstalled it? TPS is a very simple device, if it calibrates correctly then its fine.


I didn't remove it yesterday. Simply pulled the connector off it. It was re calibrated last time it was fully removed. I'll dig out the calibration info again and try And check it properly.
SonicSW20
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Re: Hesitation under initial boost

Post by SonicSW20 »

Ah, I got you.

I've only had Gen3's, but if you disconnect the TPS on those it'll hunt on idle, I don't know if Gen2 would behave the same. so perhaps if disconnecting it made no difference to the vehicles behaviour there is something wrong with it?
rossonza
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Re: Hesitation under initial boost

Post by rossonza »

SonicSW20 wrote:Ah, I got you.

I've only had Gen3's, but if you disconnect the TPS on those it'll hunt on idle, I don't know if Gen2 would behave the same. so perhaps if disconnecting it made no difference to the vehicles behaviour there is something wrong with it?



Initial unplug of the connector made the idle speed drop slightly. But it continued to idle fine. Drivability with it still unplugged was the exact same as with it plugged in.

I'll do one more test of the TPS then I'll have to take it somewhere. Don't really have a massive amount of time to fault find now. And I'm tired of throwing money at this one issue.
SonicSW20
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Re: Hesitation under initial boost

Post by SonicSW20 »

Have you replaced / tested the AFM? Searching on the US MR2 forums for heistation at 3000rpm / wont rev past 3000RPM brings up the AFM being an issue quite often.
rossonza
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Joined: Tue Dec 20, 2016 2:34 pm
Location: West Midlands

Re: Hesitation under initial boost

Post by rossonza »

SonicSW20 wrote:Have you replaced / tested the AFM? Searching on the US MR2 forums for heistation at 3000rpm / wont rev past 3000RPM brings up the AFM being an issue quite often.


Me and a friend de-lidded it and cleaned it with electrical cleaner. And I've no spare to try on it.
SonicSW20
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Re: Hesitation under initial boost

Post by SonicSW20 »

Has it run right since then? I've heard before that the AFM is pretty sensitive and opening them up isn't advisable as it's easy to break them.
rossonza
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Location: West Midlands

Re: Hesitation under initial boost

Post by rossonza »

SonicSW20 wrote:Has it run right since then? I've heard before that the AFM is pretty sensitive and opening them up isn't advisable as it's easy to break them.


Yes. The car intermittently worked fine. I thought it was related to battery disconnect/reconnect. But thats since not fixed the issue.

Example was. I went for a drive out with a friend in his 130i.

Had a race on dual carriageway. Left him for dust. Went round the corner. Went over a roundabout and my battery terminal popped off. Put it back on and I couldn't get into boost again. Then on the way back to his. Pulled into a layby. Turned car off/back on and boost came back. Then 10 minutes down the road it was gone again.

It's as if the ECU is going into a limp mode or something. Or it's a loose wire somewhere. I've checked all wiring. Redone grounds. Tried disconnecting/reconnection battery. Tried turning car off/on 20 times In a row. Nothings working now. I think something has been failing and it's finally failed completely.
SonicSW20
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Re: Hesitation under initial boost

Post by SonicSW20 »

Sounds like a right nightmare #-o

Have you used Mr. Two's in Willenhall, assuming you're still in the West Mids? He did some work on my old NA when I was in Stafford, seemed decent and knowledgeable.
rossonza
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Joined: Tue Dec 20, 2016 2:34 pm
Location: West Midlands

Re: Hesitation under initial boost

Post by rossonza »

SonicSW20 wrote:Sounds like a right nightmare #-o

Have you used Mr. Two's in Willenhall, assuming you're still in the West Mids? He did some work on my old NA when I was in Stafford, seemed decent and knowledgeable.


It's just frustrating as it's been teasing me working intermittently.

Funnily enough a friend recommended him at lunch time today. Just phoned him and its going in next Saturday. Fingers crossed he can find the issue :thumleft:
hojoos
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Re: Hesitation under initial boost

Post by hojoos »

any kind of aftermarket boost controller on the car?
rossonza
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Joined: Tue Dec 20, 2016 2:34 pm
Location: West Midlands

Re: Hesitation under initial boost

Post by rossonza »

hojoos wrote:any kind of aftermarket boost controller on the car?


There wasn't at the time. The fault ended up being a mixture of leaky ECU caps and a rusty fuel tank.
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