Problem unknown

[jerome266]

Had my vr4 back on the road a week after doing a few upgrades...Was running fine then on a rainy day lost revs had to pull over...Would start but wouldnt idle properly. Had a lumpy kinda sound. Brother suggested water had gotten through the air filter asnd air flow meteras i had moutned the pod in the front bar...Pulled all that apart took the intake off the turbo ( had a lil water in it ) disconnected the air flow
sensor and ic pipes...tried to start it...put all back together and after a few gos at trying to start it it came right...

This happened friday and has been happening ever since
espaecially when cold, will start fine then next time i try it does it again, now i just have to turn it over a few times wait a while and it will come right...Havnt got a clue whats going on

Brother seems to think its the air flow meter or sensor

Any ideas guys?
Would be much appreciated

 

[Jonson]

Sounds like you have fucked a sensor. Why would you mount the pod in a front bar of a road car?

 

[jerome266]

Wasnt actually in the front bar...Read an article on auto speed site bout ram air and intalling snokels to get more cold air decided to try it just plumbed the pod off the 055 maf down to where it would get more cold air...I know it was a stupid idea now but thats always realised after the fact... So sensor you reckon? Do i need to find another 055 maf or the like

 

[iluszn]

I had my Pod filter in the inner guard of my GSR.. worked a treat..

 

[rob323]

Had my vr4 back on the road a week after doing a few upgrades...Was running fine then on a rainy day lost revs had to pull over...Would start but wouldnt idle properly. Had a lumpy kinda sound.

What were the "upgrades"?
When it goes "lumpy", is it running on just 3 cylinders instead of 4?

 

[EVO-00X]

First check the condition of the spark plugs and leads. Also make sure the AFM and CAS plugs are in properly and no wires are damaged.

 

[killa]

hey guys the upgrades were

walbro pump, 055 Maf, 720cc injectors(cleaned and flow tested before install), small 16g, intercooler+piping. single board ecu with Razza chip.


Yeah Rob it sounds as tho its running on 2/3 very spluttery.

its just weird that it comes right after winding it over and running it for a minute.

My first thoughts were AFM not sending the right signal so unplugged it and it started ran fine, but then next time it happened i unplugging the AFM and it didnt fix it.

it also thought it may be a leaky injector but they werent leaking when cleaned and flow tested. It also starts first time in the morning but after a 15min drive, stop try to start it 5mins later and its spluttering.

As i said turn it over a couple more times run it for a minute and then it comes right runs fine??

 

[rob323]

Jap spec single board ecu, or Aus spec ecu?

As mentioned above, check all the connections on your sensors, coil pack leads, ecu etc.

 

[CLuTZ]

Sounds like a rather large leak in your intercooler setup. Check that the J-pipe coming off the turbo is sealed properly, also any joiners or hoses that might have split or are loose

 

[killa]

j-spec single board ecu.

will check out all the electrical plugs and leads etc.

Wouldn't leaking cooler piping effect it more when on boost than at idle and on start up? will double check everything is tight.

 

[CLuTZ]

j-spec single board ecu.

will check out all the electrical plugs and leads etc.

Wouldn't leaking cooler piping effect it more when on boost than at idle and on start up? will double check everything is tight.

I've had a huge leak at the J-pipe which made the car sound like it was running on 2 cylinders, laggy and wouldnt idle....

 

[rob323]

j-spec single board ecu.

Ha ha , welcome to the club of back firing J spec ecu's.
http://4gtuner.com/site/showthread.php?t=8986

Mine stopped doing it when I put an Aus spec ecu in it .

All I can think of, is that when starting, it squirts some fuel into a cylinder which is not ignited (it may be on it's exhaust stroke for example) and fouls the plug. I found that if I stopped my car, as soon as it did it, and pulled the plugs out, one was always wet with fuel, and it wasn't always the same cylinder either.
I also had the injectors checked for leaks and they were fine, but sometimes my car would do it after only being turned off for a minute, which means you would have to have a really big leak from an injector to cause that.

Yes it sucks and it's embarrassing at times. I don't know what was changed in the A spec ecu's for them not to do it, but I haven't heard of any A spec vr4's having the problem.

 

[killa]

Interesting read thanks Rob!

That explains why it hasn't done it and has been running fine for a few days then!

Thanks for the help guys!

 

[rob323]

The only bit which still has me stumped is that mine has only ever done it when starting it. It has never died while running like the O.P's did.

 

[jerome266]

Strange

Interesting read rob !
Thanks for all the helpfull information guys.
Its defenitly like theres a gremlin hiding somewhere
Hasnt done it again sinceit s been fine weather
Not sure if that makes any difference...haha
But the reassurance that something isnt majorly wrong has my mind at ease... Hope its gone forever...touch wood