Cat 1.9 Misfire And Poor Mpg

[camgti 56]

As title suggests.

 

Start the car when cold. High idle, which quickly becomes a low/struggle ( within 30 seconds ). Drive the car, very rough, no power, same all through the revs and does not want to rev either. Better on light throttle. No torque or willingness to go! Sounds like its being strangled.

 

Have tried changing AFMs ( x3 ) with no luck. Have triple checked for leaks and there are none. Have changed injectors, fuel rail, regulator, filter, plugs, leads, all with no difference. Changed O2 sensor with no difference There was a slight difference when changing the fuel rail/reg, nothing to write home about though.

 

Fuel consumption is terrible. About 200 Kilometres from a tank. Backfires on over run

 

 

 

Some more info. The fuel pump dies not prime when you turn the ACC on. Every other ( x5 ) 205 I have owned has primed. Could this have something to do with it.

 

Cam timing perhaps?

 

The car is a mates ( my boss actually ) and we bought the car for him eventually to get on the track. We also have a VTS motor ready to go in but are waiting for a few things to be made up etc for the conversion. So in the meantime we want it running as its been a s*itter ever since we bought it!

 

Any help would be great!

 

Cam

Edited June 4, 2012 by camgti

[numbum 0]

Hiya pal sounds like your having fun well you've nearly checked everything by the sounds of it but i'd defo double check the timing and then thats one less thing to throw in the mix you can rule that out then.

 

 

Sometimes the little horrible igintion amp can give you these problems as a lot of people on here will tell you it will lead you to check everything else on the car when its just this playing up. well worth a check.

[camgti 56]

Ok cool. Should I replace it or is there a way or checking it working correctly...

 

 

Cam

[numbum 0]

personally i'd just try a second hand one as there are a few aftermarket ones that are rubbish so you could fork out the dosh and have no results.

 

I had a simalar prob on my motor and spent a fortune on replacing everything even buying an orignal bosch amp the best part of 70 quid and still gave me a misfire and rough running between 3000 -5000 below or above it, in the end i ended up swapping my coil (another brand new part) with an old can type and woopee!! job sorted for now.

 

Also a problem i find is you start trying and throwing everything at it, so i just take a step back and one thing at once if all your fuel side is good pump-reg-inj-relay-etc and you've checked for leaks and your happy, your know your looking electricial side hope this helps

[Andrew C 1]

Just my 2 bobs worth but have you had the alternator tested. I had exactly these symptoms but were fixed with a replacement. Good luck as I know how frustrating these problems can be.....

[pug_ham 245 3 Cars]

Basic thing, are the HT leads in the right order / positions on the cap?

 

g

[camgti 56]

Im going to say yes but will double check the leads. Do you have a picture of guide I can follow to make sure?

 

Is there any way I can test the alternator without taking it out?

 

Cam

[pug_ham 245 3 Cars]

The pic shows an Mi but the order & cap positions are the same on the 78v.

 

g

[camgti 56]

OK. Changes the ECU temp sensor and its much better. Far from prefect but much improved. Most of the backfiring is gone. More power but still not super keen to go. Seems to be running quite rich so I will investigate the AFM mixture screw? In to lean out? Will also clean out the idle screw as the idle is pretty poor too. Could the CAT be blocked and causing it to not want to rev and sound like its being strangled?

 

Ill also check the fuel return pipe to make sure this is not blocked, apparently this can cause poor mpg and also rich running similar to what I'm experiencing...

 

Thanks for the pic Pug_Ham, ill double check tonight.

 

Cam