dave99

Hi All,
My friends Cossie 3 door failed the test on emissions. The CO reads 9.13% and HC 584 ppm!!
When the mixture is lowered at the ECU, the engine develops a misfire, causing the CO and HC to rise.
The injectors have been checked, my leads rotor and cap tried and plugs changed.
All ECU pins have been checked for faults.....


The primary ignition has been tested and is ok, secondary ignition shows a misfire
Has anyone here experienced this?


Are we barking up the wrong tree!!!


Thanks,


Dave

Stu @ M Developments

iTrader: (12)

Have the greys had the fitting kit correctly modified to work in a YB?

dave99

No Stu,
The car is running yellows with a stage one chip.. The car has not been modified in years and always passed the annual test..
Thanks,
Dave

Stu @ M Developments

iTrader: (12)

I have no idea how I read in your post that the car was on 403s. What an idiot, sorry.

Have you checked the carbon brush in the dist cap?
If your main HT voltage is down then lowering the mixture can result in a misfire.

That said, so can turning the mixture screw too far when you have a sensor failure which, if this is a sudden problem is also quite likely.

This is one of those problems where it's probably cheaper and faster to just get her on some good diagnostics that can read weber properly and see where the problem lies.

dave99

Thanks for that Stu, sorry for the delay in replying, really busy at the mo....


Jimmers from here has loaned me a phase sensor, air and water temp sensor, map sensor and a fuel pressure regulator to try out.


I took my own ECU out to try also...


The Cossie was blowing out smoke and soot and the plugs were black. There was a really bad smell of petrol also.
Checked resistance on coolant and air sensors at different temps and both seem ok.
Next to try was fuel regulator. The pressure had been tampered with so changed for Jimmers one. Ran the car for 20 mins, no fuel of smell and exhaust soot and fumes are gone. Plugs appear to be free from deposits and are brown in colour...
So all looks good in the hood!


The Cossie is going in to have the CO checked Sat morning so will keep you posted.
BTW, if the fuel pressure was too high and the injectors were pushing too much fuel in as a result of this, would the adjustment of the pot in the ECU reduce the injector time and cause poor running?


Fingers and toes crossed for the Co results!!


Thanks again Stu....


Dave

dave99

Sorry for the delay

I removed the fuel pressure regulator, piped to compressor and turned air regulator up until the fuel regulator started to blow off at 3.5 bar.
So all looked good....or so I thought!!
I placed the regular in a basin of water at 2.5 to 3 bar. The air from the compressor was escaping through the vacuum port.
Therefore, when the regulator is working on the fuel rail, some of the excess fuel is entering the engine via the vacuum hose!
Anyone out there selling a fuel pressure reg!!

Thanks for the help again,
Dave