Sneezing Out Of Jenvey And Bang!

[Simes 248 2 Cars]

Hi,

 

Drove the car for the first time in months and noticed a sneezing out of the bodies and a single bang out of the exhaust on trailing throttle.

2 months later I've found time to look at it.

My suspicion is it is running lean on one cylinder, it only happens on light throttle and trailing throttle, performance is not hindered in anyway or form.

 

 

I can replicate the fault at idle.

 

So far I've:

 

Swapped the injectors over.

Checked the bodies if they are still balanced - they are.

Played with the air valve of the body causing the issue.

Sprayed carb cleaner around the joins and tightened up the inlet manifold 1/4 turn on each bolt / nut.

 

I haven't had the chance to go out and drive it but it still misses a bit on idle.

Any other thoughts whilst rain stops play?

[Tom Fenton 1,561]

Personally I would compression test it just for peace of mind. Hopefully like you say it's a fuel fault of some kind.

[boldy205 75]

Ignition side?

[Simes 248 2 Cars]

Personally I would compression test it just for peace of mind. Hopefully like you say it's a fuel fault of some kind.

 

Yep - good call.

The missing is on no.3.

 

4. 190

3. 185

2. 180

1. 200

 

Weirdly the electrode in plug no. 1 snapped so that's game over until I get a new set of plugs.

[Dizzee stuff 33 1 Cars]

I had a similar problem, the air screws needed setting up correctly.

[welshpug 1,677]

air screws arent used on mine at all, all done on throttle stops.

 

shouldn't touch any of it unless you are a mapper, other than plugs and injectors of course.

 

werw the injectors you used tested?

[Simes 248 2 Cars]

Injectors were cleaned prior to install.

Going to check coil pack.

[jackherer 543]

Have you driven it much since you fitted cleaned injectors? I've heard a few times now of cleaned injectors that have been left for a while without being used causing problems.

[Simes 248 2 Cars]

Have you driven it much since you fitted cleaned injectors? I've heard a few times now of cleaned injectors that have been left for a while without being used causing problems.

 

Yes, about 6000 miles.

I also swapped two injectors over as part of my first test and the problem remained in the same place.

[Simes 248 2 Cars]

Ok, new plugs in and still bang.

Swapped ht leads around still bang.

Swapped leads on coil pack, bang.

Looked again at the engine, eureka!

Bang happens on cylinder 3, vacuum tap is on that cylinder......I wonder.

Removed pipe, engine running, block the hole and hey presto no bang.

Seems that the over braided hose had perished and was sucking in air.

Just need a new hose and fingers crossed for test drive.

 

I forgot to mention that the fuel return hose from regulator to pipe was found to be dangerously leaking, pissing out on the floor. This was a Teflon braided hose, since replaced.

 

Moral of the story, drive your car more often to avoid things disintegrating in front of you.

[Miles 331 1 Cars]

I don;t know what it is with Fuel pipe these days, I had a car I did 6 to 7 years ago with Gates Injection hose and the car stood for 2 years and the pipes had more hole in than well .......

[Simes 248 2 Cars]

I don;t know what it is with Fuel pipe these days, I had a car I did 6 to 7 years ago with Gates Injection hose and the car stood for 2 years and the pipes had more hole in than well .......

 

The vacuum one was one I had from 2004 when the original 16v conversion was done!

The teflon one was from 2009.