Basically my engine was dyno'd at Harveys, I fitted the engine, installed Fuel system Hayward and Scott made the exhaust and everything else has been fitted.

Its 8inj on greens, GT30 on T6 ECU.

I can start the car if I hold the throttle down and have to hold the throttle at around 3 thousand revs to keep it alive, let off the throttle and its dies. If I rev up it hesitates and misses. If I hold it for long enough to warm up it settles down and will idle but is still hesitant and misses when I rev it again.

So far I have tried new plugs, the Pectel Monitor shows no errors and neither does descpro when I connect the laptop to the ECU. The fuel pressure in the rail is 53psi with the vac hose off and 43/44psi with it on. The throttle body position is 3 degrees.

The engine was fine on the dyno and was mapped and ready to go, the only things different will be my Exhaust, wiring loom, fuel system and intercooler setup. So either somethings a miss or I've disturbed something on the engine.

Any ideas for me to try before I trailor it up to Harvey?

 

Must be a wiring issue mate, get it up to Harveys and checked over, before you start lashing out with the lump hammer.

DONT WORRY all will be simple

 

It WILL be the loom, something really silly that got missed or connected round the wrong way, as lots of the sensors require the correct polarity.

 

I tried swapping the polarity on the crank sensor and that didn't sort it, and tried it without the cam sensor and it was the same again

 

You havent got the crank sensor & phase sensor plugged the wrong way round have you?

 

hows the TPS set up on a T6?

dont know much about them but I would have a look at that going on what you have said so far

 

It shouldn't be any different from when it was set up on the dyno

 

i meant the wires/plug to the sensor.

Have you tried disconnecting anything to see if it will idle better? i.e TPS or ISCV

 

I haven't tried no, I've got another ISCV to try aswell, that was the next thing, will try at lunch time

 

What's the map sensor reading on the monitor Paul?

 

is the CPS new?

 

1.01bar then about .4 whne running, it goes up and down with revs. How ever it doesn't seem to be makin positive boost when reving up but its so missy and hesitant I may be wrong will check this

 

Its a 1-36 YBP pulley using a YBP CPS bracket and what I thought was a YBP sensor but I was later told by Harvey it was a Zetec Sensor, it worked fine on the dyno and I have tried swapping the contacts on it

 

is it earthed?

 

Actually no its not as I was told it didn't need to be by Fraser, he said that some Rally cars have them cable tied to the roll cages etc and are not earthed. I will try earthing it if you think it will make a difference also the same question for the coil pack does that need to be earth as again its not

 

even if cable tied then they are still earthed.

fraser told me he was coming to fix my evo in mid august also.and he still hasnt shown up!!!

you need to get another mar sensor and earth it before you start it.the one you have now may be fooked.

 

What about the coil pack?

 

Paul, what sensors are you using that wasn't used when it was dyno'd? Map sensor was my first thought (already mentioned)

 

Do they need to be separately earthed, I reckon not.

 

Coilpacks can go duff just like that, mine was working fine one day, missed a few times whilst driving, then ok again, next day wouldn't run clean until fully warm, changed to ACCEL 140018 coilpack, perfect ever since, even tried old one again, duff, so bin it was.
Did you actually SEE it running perfectly yourself ?
Tps may have been accidentally nudged a bit out, but go into TPS set up, then just a press of the accelerator and release and all is aligned again, you have the software on a laptop ?, worth checking this, as often overlooked.
tabetha

 

so why is there an earth on one of the bolt holes?

seen this about 20 times on rally cars that have had the sensor cable tied to the strut brace with no earth,missfire and behave exactly as paul describes above,change the sensor,add an earth and problem solved.

of course iam not saying that this is the problem here,just offering advice based 100% on experience of cosworths i have had over the past 18 years rallying them.maybe rally cars are different but boreham earthed all their map sensors on a seperate earth.

 

and check the tps is saying 3 degrees +,as they will read - as well.

 

I've only gone a sorted it.... I think

Get fucking in!

I wound the throttle cable back to 7 degrees open and all the symptoms have gone!!

Revs fine no hesitance or missing!

Must be I disturbed the TPS when I had the inlet powder coated so just got to reset it all and get it back to 3 degrees and working

 

D'oh!

And my loom suggestion wasn't a diss at Fraser, as I have even had one of my Pectel looms wired incorrecly for polarity on the TPS . There's so many wires that sometimes one can be done incorrectly .

 

Maybe shielding but it doesn't stop the operation of the sensor.

 

Ok so now I have worked out the problem whats the proper way to reset the TPS, Cable and Idle screw?

I was going to get the car to idle at 950/1000 revs buy adjusting the cable and idle screw and then the move the TPS so its reads 3 degrees but I doubt thats the proper way to do it whats the correct procedure on this?

 

As I said do you have the software on a laptop, if so, it should(if it has this feature) just be a auto calibration, through TPS/ECU config, although I have a different tps to a cossie on my cossie, it is but a 30 second job as above on my ecu, assume yours has a similar thing ?
tabetha

 

I have no idea actually would make sense if it did. How is it done manually thou?

 

You don't need to do it mechanically (other than ensuring you have full sweep).. you linearise the sensor inside DESC.

 

I'm told NOT to touch the TPS via Descpro as it would upset the mapping done on the car, there is nothing wrong with the mapping its a mechaical upset that needs adjusting.. which has just been explained to me how to be done so wish me luck :Cry:

 

Paul, the way I would do it would be to have the throttle totally closed (leave cable off). Set the TPS to show 3 degrees in this position on Descpro. The reconnect the cable and check you get the full sweep. I think you will get approx 86/87 degrees max.

Then with the ISCV (not sure if your using the ISCV for idle or ALS?) disconnected, using the air bypass screw set you idle to around 1000/1100 RPM. Job done.

Give me a shout if you get stuck with descpro and and settings/features and I can pop over.

Stu

 

Thats exactly how I was told to do it bar having the engine at normal running temps before adjusting the idle. Luckily I have a T6 pectel monitor with a remote screen that I can view the TPS position with Descpro
I'm told adjusting the TPS in situ is a job for Jeremy Beadle's hands thou

 

On some systems(mine) it is just a press on the throttle then release, job done, mapping 100% spot on, as it calibrates itself.
tabetha

 

Glad you ahve it sorted now, thought it might have been something to do with the TPS

 

Ok interestingly I warmed the car up and let it idle. Wound off the throttle cable and took it off and the TPS was at 3 degree's so the sensor was ok after all. To make it idle I had to screw the idle pin in a lot. So all I could think of was the idle valve was stuck shut. I swapped it with a ISCV a mate lent me and adjusted the idle screw again and its mint and at 3 degree's I tested the ISCV I took off and it was working fine so I'm a little stumped now as to what was causing the problems.
The only think that slightly concerns me as to whether its normal or not is anything that uses power.. fans, lights heated screen etc makes the car idle much lower as low as 700 and when that low if you blip the throttle is has a very slight hesitancy to start with but revs straight through it.

 

Give it to your mapper as it was only done on the dyno, it is not uncommon to need to tweak these areas after putting in the car.

Mark

 

are you getting it fully checked over Paul now its all done.

whoever checks it can set the throttle etc....

 

T6 has closed loop idle speed control, and is one of the things that as Mark has said needs setting up in the final in-car mapping (along with cold start etc).

 

Cool, its just due to recent events I'm a idle hypercondreact

It will go back to Harvey asap