Jenvey Bodies May Need Refurb?

[Tom Fenton 1,542]

Plugs/leads/coilpack etc all three years old?

 

Obviously there is a problem somewhere, you are unlikely to solve it by guessing, so your other option is to datalog fuelling when it is stuttering and find out what is happening.

[kyepan 291]

took a vid earlier...turn the sound up and you can here my problem

 

also only does it when the engine gets up to temp

 

Might be worth getting the multimeter out and following the caps program guide thing on the xu board sticky to check the water temperature sensor, as that could cause it to overfuel on low throttle when warm..

My pulsar did the same thing when i put on a dump valve that was leaking.. exactly as you've got, neutral throttle... ug ug... purrrrrrr ug ug... so as previously mentioned could be an air leak too. where you might get that on a throttle body inlet with no AFM i'm not sure though.

[base-1 17]

He said it done it before it went to longmans also but not as frequent. Howcome longmans never touched the fuel map?

 

Done what, changed all the water, air etc sensors? No mention of that....

 

Check everything is properly dry. If Longmans balanced the bodies OK then it's pretty unlikely that they will be wrong on only marginal throttle but fine at idle/half - full throttle. Did you only cover the bellmouth with gloves?

Edited March 24, 2008 by base-1

[GTI6BOY 29]

so as previously mentioned could be an air leak too. where you might get that on a throttle body inlet with no AFM i'm not sure though.

 

by one of the bodies having wear in it...this is what ive been told the problems is likley to be

 

base-1 - year its fine on idle and its fine over 50mph

 

i just covered the trumpets yes

[base-1 17]

Or by the manifold not being sealed against the head perfectly, or the bodies not being sealed against the manifold perfectly, or one of the fuel injectors not being sealed into the bodies perfectly

 

Also check the injectors and any other plugs you didn't cover to make sure there's no water trapped in there

[GTI6BOY 29]

Checked all that!

 

Ive taken two more better vids...the first one is the bodies flaming, while driving everytime it does it the car pulls back

 

The second vid is so you can here what is happening through the exhaust, this is being held on about 2k rpm

 

 

gonna try and get the car back to longmans in the week

[taylorspug 7]

Timing looks miles out to me...

[welshpug 1,661]

Is the crank pulley original?

[GTI6BOY 29]

no its a rich w special

[taylorspug 7]

Either the ignition is running too much advance or the cams arent dialled in correctly in order for it to be spitting back out of the 'bodies like that.

[j_turnell 137 3 Cars]

i'd get your ignition and cam timing checked if i was you.

[James_m 0]

At least you can say the bodies are ok, as its happening on all of them by the look of it. Id expect Longman of all people to be able to give you some decent advice on what the problem is.....

[GTI6BOY 29]

cant be the timing can it as i had cambelt done two days before and it was driving fine

[taylorspug 7]

It is definately timing related. After seeing that video there is nothing else it can be. Send that video link to Longmans, they will say the same.

[GTI6BOY 29]

would they have touched the timing or is it a manual thing?

[taylorspug 7]

Cam timing may have been done wrong when the belt was fitted, ignition timing is part of the engine map. What did you say Longmans hadnt touched when they mapped it? Is it on std cams?

 

It looks like cam timing, as in the first video you can see what looks like air/fuel mix being purged back out of the 'bodies unlit (before the flames start), which would suggest the cylinder is coming up on the compression stroke with the inlet valve still slightly open, pumping the air/fuel out.

 

Id get the belt cover back off and check the cam timing hasnt slipped or been done wrong when the belt was changed.

[GTI6BOY 29]

has uprated cams

 

longmans use a base map first which is used on all gti-6 throttle bodied cars then they live tweek it on the road.

 

did not start to notice problems till about two days after mapping and cambelt was done about 5 days before mapping and was defo running sweet as for those 5 days

 

going to longmans friday

[GTI6BOY 29]

All fixed now and its running sweet as a nut

 

There was a problem with the map at 2800 rpm

 

I also now have launch control fitted and it sounds unreal

[welshpug 1,661]

you're gonna have to do a vid of that!! Edited April 2, 2008 by welshpug

[j_turnell 137 3 Cars]

Yeh a vid on full chat would be nice

[Bonzai 2]

how does launch control work? i seem to recall needing the abs hubs to use traction control, is it similar to that?

[GTI6BOY 29]

Max torque on my car is 5600, an extra rev limit is set to 5200 while holding button. Foot flat on the floor, release button and you launch at max torque!

 

Sounds awsome

[Dream Weaver 2]

Glad its sorted, I think you need to sack whoever said it was a worn throttle body

 

You would do well to read a few books about engine management even if you don't plan on doing any mapping yourself - I'm no expert, but its amazing what you can learn about fueling/timing from reading a few books/websites.

[GTI6BOY 29]

right...

 

has been running sweet for the last week but has now started to do the same thing???

 

My little knowledge i know on mapping, i was under the impression that the map cant change unless its put on a laptop?

[Bonzai 2]

i would say if somethings changed its almost certainly component failure of some description