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Help - Car running really rough - overfuelling?


Pixelfill

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Hi guys,

 

I've just spent all day fitting my new Defis from Nic, (Controller, Boost Gauge, Oil Temp) and my UEGO Controller from Lucifer, and when I put the car back together it's running really rough, at idle when you turn the car on I'm getting about 14.8 AFR (This is good yes) but the car is idling at 600 rpm from first turning her over, this is unusual for my car.

 

if I start to increase the revs the AEM gauge goes all over the place, and in some cases drops off the bottom of the scale (10.something) There is a serious smell of petrol, and if I take her up to where tubby no. 2 should kick in, I'm getting no positive boost, yet I still get a report from my SARD BoV :confused: Thanks to the Defi Peak function I can see I'm only getting a peak boost of 0.

 

I disconnected the new vacuum hose and reconnected my mechanical "Spitfire" gauge, using the original vacuum hose and I'm seeing the same, no positive boost.

 

When I come off "boost" the engine feels like it's about to stall, and the AEM UEGO drops off the bottom again.

 

Can the electrics cause these symptoms ?

 

I wired the Defi into the clock feed,

Defi - Loom

Red - Red

Black - White/Black

Orange - Blue/Red

White - Green/Orange

 

as in this thread

 

I haven't set the dip switches on the controller as I interpretted that as being relevant only for the tacho (is this my problem ?)

 

The UEGO feeds are taken from the cigar lighter

Red Spliced into the positive cigar lighter through a 10A Fuse

Black Spliced into the White/Black cable on the Cigar lighter (I assume this is Earth - or should I just connect to the Chassis ?)

this is also being used as my earth for the Serial (Blue) Cable

and the White is left unconnected.

 

Please help - I'm feeling really down at the moment, the weather is good, and I was hoping to go for a run out this evening, but I can't :(

 

Cheers

 

Mike

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Hi Col, thanks for the reply.

 

The new boost Gauge is Electrical, replacing a mechanical boost gauge. The Vacuum hose is connected to the same point as the old mechanical gauge was, I never had any problems with the old gauge, but I don't know whether it is connected to the optimum location. It is 'T'd off on the top of the left had side of the Plenum (I'll get a picture it's easier)

 

The UEGO sensor was fitted by Envy last week, into the first DeCat pipe, I have only just had the opportunity to wire up the Controller, so couldn't comment on the condition of the sensor I'm afraid, but there were no boost problems coming back from Envy, so I'm guessing it's either electrical, or I have dislodged a vacuum hose (or there is a leak)

 

Off to get the photo.

 

Mike

General.jpg

closeup1.jpg

closeup2.jpg

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Mike, if you've disconnected the battery, you'll have reset the ECU, this will cause the car to run rough on tick over as you describe at first.

 

The ECU will need a few miles of driving to relearn the settings, hopefully this will sort out the problem.

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Nic - you're a genius, I never thought of that, this is the first time I've disconnected the battery. so that would probably explain the rough running, but would it explain the boost not going above 0?

 

Please say yes

 

Mike

 

no... sorry missed that bit of your post,.

 

Recheck the pipes you have disconnected and make sure they have all been refitted and that there are no leaks. Also recheck that you have followed the installation instructions correctly.

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double and triple check you have not disturbed something, the gauges you have fitted should not cause these sypmtoms (even if you made a balls of it, they only give YOU info, not the car)

 

The boost gauge sensor takes a feed off the turbo vacuum hoses, which if fitted incorrectly or if there is a leak, would result in drop or no boost.

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Good News...

 

I've just had a quick run around all the vacuum hoses checking for loose connections. Couldn't find any, but I replaced the short see-through tube in the pictures anyway, and then took the car for an ECU learning drive.

 

Blow me if I wasn't getting positive boost (did you see what I did there ;))

 

After a good 30-45 minutes drive the car seemed to be behaving a lot better in terms of fuelling too, so I can cancel my coronary bypass for tomorrow thankfully.

 

Cheers guys for putting up with my panic.

 

Nic, I'll get some pictures up for you soon :thumbs:

 

Mike

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