Rowans GPX Turbo Build

[Rob Furniss]

Car isn't running rich anymore now that the exhaust has been fixed, well it is a little rich but not loads.
Idles high until it starts to warm up and then starts to drop the revs and got to around 1000, then once warmed up it started to hunt by quite a lot and then died.
I started it again and it was better, settled at around 900rpm and afr is at 12.5:1 on the wideband, I left it like this for a few minutes and it was steady.
Then blipped the throttle and it coughed and spluttered and then died again, what should I check first?

No error codes showing.

Also I was going to get an ignition timing lamp the other day to see what's going on, would this be handy and are they easy to use on our car?

[getonit]

Had a similar issue on mine a while back. Had a leak in the map sensor hose close to the manifold. Long shot but worth ruling out

[Rob Furniss]

Yeah good one to try, i'll replace that and see how it goes, thanks.

[Rob Furniss]

Not the map vac line, replaced that and still same issue.
Unplugged the TPS and it was better (but of course won't be any good to drive like that).
Plugged the TPS back in and unplugged the map sensor - better but again no good for fixing the issue, does it help at all with diagnosis?

Still goes to sleep when throttle is pressed then released.

Going to get a gauge on his fuel pressure regulator to see what's happening there, well what I really mean is fit an aftermarket one that has a gauge, just waiting for fuel rail adapter arriving into the shop.
Also need to get the laptop hooked up to the emanage and log what's happening, maybe that will show me something, I could also try swapping out the emanage with mine to see if it helps.

[Vectose]

Is the TPS calibrated properly?

[Rob Furniss]

Is the TPS calibrated properly?

Not sure, it hasn't been changed / messed with since the engine came out and went back in.
I've done the TPS calibration in the emanage, but i'll go through the TPS reset procedure as per the workshop manual, cheers Rob.

[Rob Furniss]

Swapped the emanage with mine - still same issue.
Removed the emanage so it's just running on factory but still with the 275cc injectors - it's running a lot better, just generally sounds better.
Can blip the throttle and it doesn't stall.
But it's running rich of course due to the larger injectors, might just put the stockies back in and see how it is then and then work back up from there.

[Bennoz]

You moving your base fuel map around on the emanage with those injector changes? 166 to 275 is a fair whack, almost 60%..

[Rob Furniss]

Yeah I put the injector change values into the emanage parameters, before change 166 and after 275, it's supposed to sort it all out automatically but I read it doesn't like massive changes.
Seems to manage ok on my car though, it's just Rowans that's not coping but then again his has had all sorts of stuff done, lower comp pistons, bit of head porting and the cams from RPW. They did tell me that they were only going to put the hks 272 profile on the mivec cam so it should be running on a stock cam when idling shouldn't it.
Also wondering if we should move his stock O2 sensor and AEM one closer to the headers as the route to those is now really long, headers are meeting under the sump then going forwards and then up past his oil filter to the turbo which is where the factory airbox used to be, then exit from the turbo where the battery used to be and back down past the rear of the gearbox before it even gets to the O2 sensors. Then again if he hasn't got an exhaust leak anymore (hope not) it shouldn't be an issue.

[FTODreams]

Have a look on most turbo cars the location. The o2 sensor should not be so far away from the exhaust ports. The reason is that the sensor takes too long to respond to the process. Because it's a reactive process the further away from the combustion chamber it is the delay will cause it to be to slow in picking up changes in the stoich ratio. Hence the ECU will just overcompensate excessively. One of the reason's it might not be working on the Emanage is you have o2 sensor enabled at idle whereas the factory ECU doesn't use the o2 sensor at idle. So I'd be moving them closer.

[Rob Furniss]

O2 sensor isn't wired into the emanage we've just got it on the gauge.
I have found another exhaust leak though between the turbo and the O2 sensor so i'm sure that won't be helping.

Checked the oil pressure - looks good, 60psi when high idling and drops to around 40psi low idling.

Checked the cam timing again this time with the crank pulley off to check the crank too - all good.
What if I unplug the O2 sensor, what will it do then/what's it supposed to do?

[Rob Furniss]

Idling much better and no more stall since I removed the Magna throttle body which had the Magna stepper motor in it.
Seems you have to swap the whole bottom body of the Magna throttle body with an FTO one and use the FTO stepper. Why? The FTO ecu can't properly drive a magna stepper and you can't just pop an FTO stepper in as the plunger isn't big enough to plug the port in the Magna throttle body bottom half.
I didn't figure this out it was on an old thread.

Still a little hunting but hardly.
Still running rich but not loads, think there is still an exhaust leak to track down.

[FTODreams]

If it's not wired into the emanage its fine. If you had unplugged the o2 sensor and it was connected all it does is not use the o2 sensor to adjust fuel delivery at idle or at light loads/cruise speeds. So it just runs straight off the ECU map and nothing else.

The throttle body problem is to do with the number of steps each stepper motor has. From memory, the FTO has 80-120 and a Magna has 160-180 from memory? Those numbers aren't 100% correct but its something like that.

There is probably a few hairline crack exhaust leaks giving you trouble. I like to make sure my exhaust gaskets don't leak by giving them a light smear of RTV red.

[Rob Furniss]

He's just driven it and no issues - stalled once I think he said but I put that down to the driver (manual) or that this stepper isn't 100% but it's definitely loads better than before.

[FTODreams]

It could still be the stepper making him stall.. They take a while to calibrate with the normal ecu. And tuning the stepper from an aftermarket ECU can be equally hard.

[Rob Furniss]

Yeah I think I might try my stepper in his car and see if it's any better.
Also going to check for exhaust leaks sometime by firing compressed air up it's jacksy and spraying soapy water on it (engine off).
But his car is out of my garage now and mine is in, got a few jobs to do on mine.

[Rob Furniss]

Car is a lot better, doesn't stall when on the drive/in garage etc when blipping the throttle - but it does when he's driving slowing down coming to roundabout/junction.
Think it's when he's pressing the clutch down as he said it doesn't do it if he drops it into neutral - could it be that the clutch isn't fully disengaging the drive and needs adjusting as we really just threw it on when we did the manual conversion which was done at the same time as the engine rebuild?

Is there a good way to check/rule this out?
From what i've read on here it sounds like I need to adjust where the pedal connects to the bracket?