Help needed again please

[leeclark2010]

It was all going so well and then....after fitting the rev1 turbo lump I've been taking it easy driving into work, done 2 oil changes, checked everything weekly and now I've started to give it a little more stick to see what she's got. I let her get upto temp by driving below 2000 revs for 10 minutes or so and if I'm on an a or b road and give her some beans she is fine ( most of the time) but If I'm heading to work on the m11 and slowly build the speed up and then boot it the engine management light comes on an the power cuts completely, and will only come back if I feather the throttle. After a few seconds the light goes off and all seems well, but if I go over maybe half throttle its the same again. The odd thing is if I turn her off and straight back on all seems well, which is fine on an a road at traffic lights but a bit of a b1tch on the outside lane of he m11!! Any help appreciated. I did think maybe throttle position sensor....but that is pure speculation

[Ethan21]

Thats fuel cut sounds like your over boosting

[leeclark2010]

Sweet!! Just bought a fuel cut defender off eBay! Landed on my feet I hope

[dan4]

Perhaps fixing the excessive boost might be a better option before you kill the engine

[Ethan21]

Perhaps fixing the excessive boost might be a better option before you kill the engine

+1

Have you uped the boost then? If so how much? And What supporting mods do u have?

[leeclark2010]

No mods at all other than a Walbro 255 and a gutted cat...no mbc/ ebc.... Any suggestions?

[Ethan21]

1st thing id do is check for any air/vac leaks

If its not that maybe the actuators damaged or someones tried to adjust the arm

did u see the turbo and motor running and working b4 the conversion ?

[Peter Gidden]

Hate to state the obvious, but what fault codes are registered?

Sounds likel fuel cut to me. Easy to hit fuel cut with a decat on a Rev1/2. Even on a stock engine.

[dan4]

No mods at all other than a Walbro 255 and a gutted cat...no mbc/ ebc.... Any suggestions?

When it is cold the puny wastegate cannot get rid of the required air to control boost properly and it creeps up to fuel cut. Use some universal exhaust gasket sheet and make a restrictor up for the end of the downpipe

[Peter Gidden]

No mods at all other than a Walbro 255 and a gutted cat...no mbc/ ebc.... Any suggestions?

When it is cold the puny wastegate cannot get rid of the required air to control boost properly and it creeps up to fuel cut. Use some universal exhaust gasket sheet and make a restrictor up for the end of the downpipe

Ot fit an FCD and take advantage of the extra power from the cold air.

[leeclark2010]

Whoa, replys at 1am! I didn't see the engine running before the conversion, came from a deceased estate and had been stood a fe years, but is only 49k...car was stock other than audio. All genuine Toyota parts on her, branded tyres etc and I believe well looked after when he was on the road and garaged all her life. Can't see that the actuator would have been fiddled with, but how do I check? It only seems to be 4th and 5th gear so I'm gonna start with the FCD and see what happens. As for fault codes I haven't read them yet ( another I'm not sure how to do, will search in a moment ) thanks everyone, much appreciated!

[Peter Gidden]

Whoa, replys at 1am! I didn't see the engine running before the conversion, came from a deceased estate and had been stood a fe years, but is only 49k...car was stock other than audio. All genuine Toyota parts on her, branded tyres etc and I believe well looked after when he was on the road and garaged all her life. Can't see that the actuator would have been fiddled with, but how do I check? It only seems to be 4th and 5th gear so I'm gonna start with the FCD and see what happens. As for fault codes I haven't read them yet ( another I'm not sure how to do, will search in a moment ) thanks everyone, much appreciated!

I'd stop worring. I doubt you have any problems. Like i said, add a decat, and cold weather boosting will often exceed standard boost pressure.

[leeclark2010]

Thanks Peter, sound advise as ever. Thankyou

[Ryan S]

Fit a boost controller and decent gauge, set boost to 14psi. Set FCD to 15 psi. Job done.

[mrgarry2turbo]

Did you get this sorted in the end, exact thing happening to me. Over boosting then fuel cut, error code thrown up for throttle position sensor, not calibrated correctly, about to fit a new throttle body with calibrated TPS in a couple of hours. I'll let you know how I get on, might help your situation also

[Peter Gidden]

Did you get this sorted in the end, exact thing happening to me. Over boosting then fuel cut, error code thrown up for throttle position sensor, not calibrated correctly, about to fit a new throttle body with calibrated TPS in a couple of hours. I'll let you know how I get on, might help your situation also

I tjhink you're getting confused with terminology.

Fuel cut is triggered by the turbo pressure sensor, AKA TPS.

Throttle position sensor has nothing to do with boost and fuel cut and is AKA as TPS.

[Johnr32]

Hate to state the obvious, but what fault codes are registered?

Sounds likel fuel cut to me. Easy to hit fuel cut with a decat on a Rev1/2. Even on a stock engine.

Happened to me on my rev2 once. Never noticed until you mentioned that, I had a full exhaust and decat and thought I had blown something when it was just the fuel cut.

[mrgarry2turbo]

True Pete, my error code is the throttle sensor though but do also get code for over boost, I know its not related but y would I be over boosting if no MBC fitted, everything stock?

[mrgarry2turbo]

Tell a lie, I havnt hit fuel cut for a few days now, however if I give it throttle I struggles to go higher than 2300 rpm feels like I'm tethered to bungee rope.

But just before Xmas things were fine but hitting fuel cut.

But anyways, gonna fit new TB today redo ignition timing and see how things are then report back