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Stuart69

Car running rich - now won't start

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Hi all.

 

I've had my 92 turbo SE lots for a little over 2 years now. Sadly, I've never driven it much, as it has always been running very poor (don't ask me how I got it through 2 MOTs). It's running very rich most of the time.

I moved it into the garage just before Christmas to spend some time on the brakes (bleeding, etc). Was looking forward to getting out for a run but car won't start at all now!!

 

Plenty fuel I think (it reeks of petrol and the plugs are wet when I try). I dry them off and reinsert to no avail. I've pulled each HT lead in turn and with a spare spark plug get a spark on each one.

 

Parts replaced in an attempt to fix the rich running:-

Fuel pressure regulator

IAC valve

O2 sensor

Spark plugs are new.

 

Is it possible this is related to coil pack? If it's worth trying I wondered if any fellow owners had a spare for sale.

 

Best wishes,

 

Stuart

 

 

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which O2 sensor did you use? and which spark plugs?

 

Since you said you have spark on all 4, then it doesn't really make sense to change the coil packs.

 

You could have a cracked rubber elbow to the MAP sensor.

 

You could have leaky or poor flowing fuel injectors that aren't atomizing the fuel enough so that it can be fully ignited.

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Hi.

 

There's probably lots of info I can recall when prompted (sorry). The previous owner replaced the O2 sensor shortly before I bought it from him with the running issues). He said it was supplied by SJS (but he didn't have the receipt). I also checked the MAP sensor pipework and elbow late summer (nothing amiss). Spark plugs are Bosch super 4's.

 

I guess the injectors are a possibility, as the fuel tanks were also recently replaced for the dreaded leak issues. I would have thought I could at least get a cough out of it when trying to start it after spark plug cleaning. It doesn't even cough once.

I also took the air intake hose off the turbo and 'carefully' squirted some easy start onto the turbo while I got a friend to crank the car (again straight after reinstalling spark plugs). It felt quite risky, but still I got no cough at all.  

 

I'll dig out a Freescan run log I have from the summer when the car was running (you might spot something I haven't clicked on).

 

Thanks for the help,

 

Stuart

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Thanks for looking Derek.

 

I hadn't thought that would lead to black fouling of the spark plugs and the car running rich. When I looked at the run, I saw a lowered MAP reading (which looked OK to me), and an idle air control valve opening all the way up... but still not enough to prevent running rich as sensed by the O2 sensor.

 

BTW, I also disconnected the O2 sensor afterwards and it made no real difference (even after 2 minutes).

 

Cheers,

 

Stuart

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The IAC valve counts are always zero indicating the valve is closed in an attempt to bring the rpm down.

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agree on the air leak, making the idle totally erratic with no control via the IAC.

 

The signal from the O2 looks totally wrong as well, but I'm not sure I've seen one with an air leak that bad....  So not sure if that's just what they look like when there is no possibility of control as in a normal feedback loop.

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