Author Topic: Running Issue  (Read 8580 times)

Offline Dougy

  • Members
  • *****
  • Posts: 34
Running Issue
« on: March 05, 2008, 12:06:40 pm »
Hi Guys

This could be linked to the fuel pump which is very noisey but I'll see if anyone knows the answer

Right car drives fine and no problems until i go over about 4.5k or boosting.

After that every 5 seconds regardless if its sat ideling or driving, the revs drop for a split second.

If I am driving then it only happens if the revs are under 2.5k which makes doing 30 very difficult.

Very annoying as the car jolts asif its running out of petrol.

The only way to stop it is turn engine off and take keys out.

Could this be the fuel pump? Any ideas

Thanks

Dougy

Offline hayesey

  • Administrators
  • *****
  • Posts: 5630
  • The CV joint killer
    • ClubG40
Re: Running Issue
« Reply #1 on: March 05, 2008, 12:10:15 pm »
a problem over 4.5k or on boost could well be fuel pump not up to the job.  Do you have access to a fuel pressure gauge you can hook up while driving? Then see if the pressure suddenly drops at 4.5k or on boost?  Could do with finding out pretty soon really as leaning out could cause you a whole load more problems!

Offline Dougy

  • Members
  • *****
  • Posts: 34
Re: Re: Running Issue
« Reply #2 on: March 05, 2008, 12:14:23 pm »
[quote pid=111 author=hayesey date=1204719015]a problem over 4.5k or on boost could well be fuel pump not up to the job.  Do you have access to a fuel pressure gauge you can hook up while driving? Then see if the pressure suddenly drops at 4.5k or on boost?  Could do with finding out pretty soon really as leaning out could cause you a whole load more problems![/quote]

Well as it is a conversion and was 1.0 and then a GT I can only suspect it has not being changed

Think I will be picking one up from dan tonight and fitting it then

Would this cause shit fuel consumption?

Offline hayesey

  • Administrators
  • *****
  • Posts: 5630
  • The CV joint killer
    • ClubG40
Re: Re: Re: Running Issue
« Reply #3 on: March 05, 2008, 12:29:39 pm »
no I wouldn't have thought so, that kinda suggests you've got a sensor or two down and the ecu is in limp home mode.  Although perhaps the fact it goes a bit mad on boost or over 4.5k is giving the ecu the hump?  I think you need to get the pressure gauge on it or try that spare pump first, see if that helps and take it from there.  Could well be a non-MPI pump by the sounds of it.

Offline Dougy

  • Members
  • *****
  • Posts: 34
Re: Re: Re: Re: Running Issue
« Reply #4 on: March 05, 2008, 12:30:50 pm »
Cheers Hay

I'll stick it on tonight and report back

Offline Andy

  • Traders
  • *****
  • Posts: 1494
Re: Re: Re: Re: Re: Running Issue
« Reply #5 on: March 05, 2008, 12:35:30 pm »
When I first did my conversion the SPI fuel pump was pretty tired - and gave the exact same symptoms when booting it. Sorted it straight away by fitting a G40 pump.

You can normally pick up mechanical oil pressure gauges cheaply and use them as a pikey fuel pressure gauge. I ran with one for a while to keep an eye on things.

Edit to add...
Didn't get the same bucking around at idle though. Are all the vac hoses plugged in properly? Lambda all good?
« Last Edit: March 05, 2008, 12:37:19 pm by Andy »

Offline Dougy

  • Members
  • *****
  • Posts: 34
Re: Re: Re: Re: Re: Re: Running Issue
« Reply #6 on: March 05, 2008, 01:18:21 pm »
[quote pid=115 author=Andy date=1204720530]When I first did my conversion the SPI fuel pump was pretty tired - and gave the exact same symptoms when booting it. Sorted it straight away by fitting a G40 pump.

You can normally pick up mechanical oil pressure gauges cheaply and use them as a pikey fuel pressure gauge. I ran with one for a while to keep an eye on things.

Edit to add...
Didn't get the same bucking around at idle though. Are all the vac hoses plugged in properly? Lambda all good?[/quote]

Ye i think the pump will sort it hopefully as it whines like an hamster at the minute.

At idle you can hardly notice the drop it rev's as it is only a slight drop but noticed when it is doing the fuel pump whine becomes louder

The whole thing is very annoying when in traffic and travelling at 30mph as it tends to be low 2nd gear and low 3rd gear

I will check hoses tonight and all connections, I know the knock sensor connector is fucked so that might be causing problems too or might not even be connected but I have a spare
« Last Edit: March 05, 2008, 01:19:40 pm by Dougy »

Offline Andy

  • Traders
  • *****
  • Posts: 1494
Re: Re: Re: Re: Re: Re: Re: Running Issue
« Reply #7 on: March 05, 2008, 01:39:59 pm »
Fairly sure you can unplug the knock sensor and still have the car run fine - but it'll probably use more conservative maps as it'll know that the knock sensor input is open circuit/disconnected.

Could probably get around it by sticking a suitable resistor in the wiring loom instead.

Offline Dougy

  • Members
  • *****
  • Posts: 34
Re: Re: Re: Re: Re: Re: Re: Re: Running Issue
« Reply #8 on: March 05, 2008, 08:21:29 pm »
Anyone know a easy way to get fuel line clips back on lol

Struggling like fuck

Offline supercharged spaniel

  • Members
  • *****
  • Posts: 1034
  • GRRRRRRR
Re: Re: Re: Re: Re: Re: Re: Re: Re: Running Issue
« Reply #9 on: March 05, 2008, 08:34:15 pm »
put new jubilee clips on lol  the original ones are slags

Offline hayesey

  • Administrators
  • *****
  • Posts: 5630
  • The CV joint killer
    • ClubG40
Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Running Issue
« Reply #10 on: March 05, 2008, 09:24:25 pm »
are they those pinch clip things as standard?  If so then they aren't really re-usable, fuel pipe clips are the best bet (screw on ones) but jubilee will do at least for the time being.  The problem with jubilee clips is that you have to over tighten them to keep a seal under high fuel pressure whereas proper fuel pipe clips are designed to put a more equal pressure around the pipe and seal without being as tight.

Offline Dougy

  • Members
  • *****
  • Posts: 34
Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Running Issue
« Reply #11 on: March 05, 2008, 10:13:02 pm »
Well that was fun

Had trouble finding some small jubilee clips in the garage but finally got there

Put them on "thought" they were tight started it up and spayed fuel all over like Haysey said you need to overtighten them but unfortunatly he posted after I put them on.

So took them off and went to disconnect the fuel pump again distracted as I was talking to my friend on the phone.

And who can guess what happened?? Well put it this way now I know why birds don't like giving head!!

I got sprayed in the face with about £fivers worth of fuel and fuck me did it sting.

at this point still on phone eyes burning says to mate "I can't see i'll have to call you back"

Note to novices don't talk on phone whilst removing fuel pump

Anyway after a quick wash in ice cold water think I will do it again after this post anyway as I can still feel my eyes stinging. I put it all back together and took on the test drive to find I still have the same problem.

Any suggestions guys?

Offline DKnight

  • Administrators
  • *****
  • Posts: 1426
Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Running Issue
« Reply #12 on: March 05, 2008, 11:47:43 pm »
id say sensor issue, unplug ecu, reset it, and the take out and see if it does it straight away, i dont know how quickly limp home mode kicks in, get raes laptop to check it...

Offline hayesey

  • Administrators
  • *****
  • Posts: 5630
  • The CV joint killer
    • ClubG40
Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Running Issue
« Reply #13 on: March 06, 2008, 09:27:01 am »
yeah was gonna say, get rae on the scene with his vagcom if you can.

Offline Dougy

  • Members
  • *****
  • Posts: 34
Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Running Issue
« Reply #14 on: March 06, 2008, 10:38:08 am »
Well got up this morning started driving to work did 1 mile and smelt petrol it was pissing out of the fuel pump

Note to self never use jubilee clips