Misfire

[bozothenutter]

Can anybody identify what this is and what it does ? Because this one doesnt appear to do a great deal.

Looks like the carbon canister.

 

[Johnson.]

Looks like the carbon canister.

Sorry, i should have said. Thats sorted now... cheers. But i think we are getting close to the source of the problem here is a better picture, on the back of the inlet manifold next to tge tb.

 

[bozothenutter]

Sorry, i should have said. Thats sorted now... cheers. But i think we are getting close to the source of the problem here is a better picture, on the back of the inlet manifold next to tge tb.

That's the line that goes to the brake servo

 

[Johnson.]

That's the line that goes to the brake servo

Interesting! Thanks

 

[STEVE.M]

Interesting! Thanks :smile:

Returning to the the forum rather than PM ing,the pipe at the cambelt end of the inlet manifold is for the carbon canistor.
The rear pipe(looking at the engine from the front with the bonnet open) at the throttle body end is for the brake servo.
The front thin rubber one that runs under the battery carrier connects to something referred to as an accoustic valve(although this is probably a coincidental effect lost in translation),located at the end of the wire reinforced induction fibre hose under the left hand side(sitting in the car) of the front bumper.
The accoustic valve`s primary function is to duct warmer air from the engine bay on start up,warming up period.
Fit an induction kit,cap the vacuum take off ,and bin the AV.
Any air leaks in the 2 remaining vacuum systems(canister/servo) will reak havoc with the fuelling

 

[MicKPM]

That pipe is the vacuum line to the brake servo. That will not cause a misfire i'm afraid... start with a reliable diagnostic and check the live data parameters. Until you do this you're pissing in the wind I am afraid.

 

[Johnson.]

Thanks for the replies. Surely if the car has a vacuum leak, in this case on the brake servo line. It will cause the car to run rich thus potentially fouling plugs the and will in turn cause a misfire ? 1 thing is for the, this pipe is affecting the running of this car in some way . I will try and get hold of a diagnostic machine to read the live data parameters.

 

[MicKPM]

No, a Vac leak from any source (including this) would merely cause a high idle speed not a misfire.

More oxygen doesn't mean more fuel is automatically added. The ECU looks for this and compensates as standard by looking at the U/S H02 value vs MAP value to work out actual Load.

You're over thinking the problem before you've even had a diagnostic session.

 

[Johnson.]

No, a Vac leak from any source (including this) would merely cause a high idle speed not a misfire.

More oxygen doesn't mean more fuel is automatically added. The ECU looks for this and compensates as standard by looking at the U/S H02 value vs MAP value to work out actual Load.

You're over thinking the problem before you've even had a diagnostic session.

Take a look at this...

No, a Vac leak from any source (including this) would merely cause a high idle speed not a misfire.

More oxygen doesn't mean more fuel is automatically added. The ECU looks for this and compensates as standard by looking at the U/S H02 value vs MAP value to work out actual Load.

You're over thinking the problem before you've even had a diagnostic session.

 

[bloke]

pull the vac pipe for the servo and tickover should jump right up. did you do compression test?

 

[Johnson.]

pull the vac pipe for the servo and tickover should jump right up. did you do compression test?

Thanks to the reply. Yes i did compression test and all 4 cylinders read 180 give or take 5, so i am satisfied with that

 

[STEVE.M]

Thanks to the reply. Yes i did compression test and all 4 cylinders read 180 give or take 5, so i am satisfied with that

How does it run with the air filter box removed?If it was my problem,I`d stop wasting my time,put in some overtime & hand it over to Mick at Diamond,just up the road from you.

 

[Johnson.]

How does it run with the air filter box removed?If it was my problem,I`d stop wasting my time,put in some overtime & hand it over to Mick at Diamond,just up the road from you.

Thanks Steve. Runs no better with the air box removed. I can appreciate what you are saying but Mick is a good hour away from me and the car is currently sorn, i wouldnt hesitate otherwise!

 

[STEVE.M]

Thanks Steve. Runs no better with the air box removed. I can appreciate what you are saying but Mick is a good hour away from me and the car is currently sorn, i wouldnt hesitate otherwise!

Well that rules out the accoustic valve.
I thought you had access to a trailer or similar,as you bought the car as a non runner,but got it home.

 

[Ol’ Tarby]

You checked the timing yet?

 

[Johnson.]

You checked the timing yet?

Yup - Saturday morning. Nothing to report, everything as it should be. It seems to me like an air intake problem. When the car is up to temperature and you disconnect the brake servo vacuum pipe, it draws more air into the intake manifold. Put the hose back on and the misfire and idle sorts itself out, until you stop the car and restart it. Repeat the above process and the car is fine again.

 

[Johnson.]

Well that rules out the accoustic valve.
I thought you had access to a trailer or similar,as you bought the car as a non runner,but got it home.

Unfortunately not. Paid a recovery company to collect and drop the car.

 

[Johnson.]

Sorted!!! Bent pin on the MAP sensor... thank you all for your help.