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loss of power in low rpm range O/D and slip control flashing


jacob360
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Before i start the car is a 1995 import factory TT auto with bpu upgrades. No engine codes!

 

 

Problem first realised one morning turned the car on O/D and slip control light flashing and idle is rough, the car is power cutting where the first turbo acts, it will slowly rev to about 2000rpm then holds back, it wont rev higher but will create and hold boost to about 10psi, if you go WOT the car will drop a gear and slowly build rpm to where the second turbo comes in and then car will drive normally to the red line- flashing lights remain on the whole time.

 

The first time this happened i removed the negative terminal for an hour and problem solved, i went for a day out and did about 150 miles no issue, next morning problems re occurred, disconnecting the battery also no longer solves the issue.

 

So far i have looked for obvious vacuum leaks, split pipes and loose connectors but cant see anything

 

I have removed the two solinoid valves infront of the first turbo and bench tested them and they work as should. i have tried the mod to go from sequential to parallel turbos and there is no difference in the problem

 

i have checked by hand the throttle position sensor to see if this has slipped and it looks to be correct with original paint pen marks.

 

What should i check next? i do not know if this is a sensor issue a wiring issue or mechanical? could it be a turbo/ actuator issue? i have heard the speed converter may be worth looking at? so i will next remove the cluster and see if i can see anything obvious there.

 

what next?

 

my personal feeling is this is electrical but its only a hunch

 

i will keep this up to date with what i have checked and with the resolution when i find it.

 

Many thanks in advance!

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Jackso11 is based in Norwich NR6 6RF, he has an ECU of mine that was giving me a "no fourth gear" issue on my car, but everything else was running fine.

 

He has used it to verify his ECU was causing the issues, it was as putting mine in sorted his idle and general running issues. PM him and see if he'll send it to you so you can check yours?

 

http://www.mkivsupra.net/vbb/showthread.php?352099-No-boost-help!/page2

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Jackso11 is based in Norwich NR6 6RF, he has an ECU of mine that was giving me a "no fourth gear" issue on my car, but everything else was running fine.

 

He has used it to verify his ECU was causing the issues, it was as putting mine in sorted his idle and general running issues. PM him and see if he'll send it to you so you can check yours?

 

http://www.mkivsupra.net/vbb/showthread.php?352099-No-boost-help!/page2

 

Great thanks for that! I will send him a message

 

 

 

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Mine wasn't losing power like yours but had the engine management light on and Slip Cont Off and O/D Off flashing.

Turned out to be poorly adjusted throttle position sensor and faulty cam sensor.

 

I had a look at the TPS yesterday and doesn’t looked to have moved at all and is all tight so I will look at the cam sensor!

Thanks

 

 

 

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Couldn’t get to the cam sensor so that will have to wait to the weekend, what am I looking for on the cam sensor?

 

I did unplug the TPS and the idle control one by one, idle didn’t change.

 

Removed the blow off valve and plugged it and it ran worse, so that seems to be fine. Did seem to get a knock at low revs on initial cold start so I took the coil cover off and the first coil pack does have a bolt missing but if it was miss firing surly I would have an engine code?

 

Next I’ll look into the speed converter and fcd wiring to see if anything is badly connected there

 

 

 

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Couldn’t get to the cam sensor so that will have to wait to the weekend, what am I looking for on the cam sensor?

 

I did unplug the TPS and the idle control one by one, idle didn’t change.

 

Removed the blow off valve and plugged it and it ran worse, so that seems to be fine. Did seem to get a knock at low revs on initial cold start so I took the coil cover off and the first coil pack does have a bolt missing but if it was miss firing surly I would have an engine code?

 

Next I’ll look into the speed converter and fcd wiring to see if anything is badly connected there

 

 

/QUOTE]

 

Garage Whifbitz sorted mine as it had been elsewhere and not properly diagnosed.

 

The TPS sensor was only fitted with one screw after it had suppose to have been adjusted elsewhere previously (obviously not put the other screws in, nor set it right!). With the sensor being loose and not adjusted correctly it was causing the Slip Cont Off & O/D Off lights to flash. The TPS sensor is set up by using a multi meter I think. I'd be tempted to ask Whifbitz how to check and set it correctly, just in case it was never set properly to begin with.

 

With the Eng Management light on the fault codes showed Cam Sensor. Not sure if they tested the sensor with a meter or just plugged a new one in. Again, I'd be tempted to call them, as Paul and Dan were very helpful after me scratching my head for months after being told by another place that all the faults were my Engine ECU.

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Garage Whifbitz sorted mine as it had been elsewhere and not properly diagnosed.

 

The TPS sensor was only fitted with one screw after it had suppose to have been adjusted elsewhere previously (obviously not put the other screws in, nor set it right!). With the sensor being loose and not adjusted correctly it was causing the Slip Cont Off & O/D Off lights to flash. The TPS sensor is set up by using a multi meter I think. I'd be tempted to ask Whifbitz how to check and set it correctly, just in case it was never set properly to begin with.

 

With the Eng Management light on the fault codes showed Cam Sensor. Not sure if they tested the sensor with a meter or just plugged a new one in. Again, I'd be tempted to call them, as Paul and Dan were very helpful after me scratching my head for months after being told by another place that all the faults were my Engine ECU.

 

Thanks I have spoken to them and they said they would obviously need the car to diagnose only issue is I am on the opposite side of the country

 

 

 

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Thanks I have spoken to them and they said they would obviously need the car to diagnose only issue is I am on the opposite side of the country

 

 

/QUOTE]

 

Yeah I know that feeling, usually a 7hr round trip for me when I go and drop mine off.

 

You could also try SRD if they're closer.

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Yeah I know that feeling, usually a 7hr round trip for me when I go and drop mine off.

 

You could also try SRD if they're closer.

 

Getting some quotes from both is looking likely it will go to one of them, starting checking coilpacks and the loom plugs just started to disintegrate haha, jobs slowly slipping out of my hands anyway

 

 

 

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