Please Help Diagnose a problem - JDM STI7
04 May 2004, 02:44 AM
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Please Help Diagnose a problem - JDM STI7
Hi all,
I have a JDM STI7. Full ScoobySport catless turbo back zorst and remapped ecu with uprated fuel pump.
History:
Had a hesitation and breakdown feeling under load about 5000 miles ago. Replaced the factory sprak plugs with exact replacements and it solved the problem.
Recently thought I heard det so posted some logs on here and some of the pros said that everything looked good. I will be installing a knock link in about 2 weeks (waiting for it to arrive).
A new problem has just come up:
1) I hear a whinning / buzzing sound coming from the rear of the car. I have no idea what it could be. It doesn't happen right away when I start the car but then in a few mins I hear it. I am pretty sure it is coming from the rear of the car and I can't hear it from the engine bay. You can hear it when car us parked in neutral and the pitch etc increases when the go peddle is pressed.
Only thing at the rear of the car are the brakes, zorst and differential correct ?
My guess is possible zorst leak as the pitch increases even at a stop in neutral when the go pedal is pressed so brakes and differential ruled out ?
2) My car is breaking down under load again. I think it is the spark plugs again. Why would they fail so quickly again only 5000 miles since changed ? Do I need to change spark plug type / gap size etc ? Is there anything else that could be causing the plugs to fail ?
Thoughts and advice please.
Cheers,
Ray
I have a JDM STI7. Full ScoobySport catless turbo back zorst and remapped ecu with uprated fuel pump.
History:
Had a hesitation and breakdown feeling under load about 5000 miles ago. Replaced the factory sprak plugs with exact replacements and it solved the problem.
Recently thought I heard det so posted some logs on here and some of the pros said that everything looked good. I will be installing a knock link in about 2 weeks (waiting for it to arrive).
A new problem has just come up:
1) I hear a whinning / buzzing sound coming from the rear of the car. I have no idea what it could be. It doesn't happen right away when I start the car but then in a few mins I hear it. I am pretty sure it is coming from the rear of the car and I can't hear it from the engine bay. You can hear it when car us parked in neutral and the pitch etc increases when the go peddle is pressed.
Only thing at the rear of the car are the brakes, zorst and differential correct ?
My guess is possible zorst leak as the pitch increases even at a stop in neutral when the go pedal is pressed so brakes and differential ruled out ?
2) My car is breaking down under load again. I think it is the spark plugs again. Why would they fail so quickly again only 5000 miles since changed ? Do I need to change spark plug type / gap size etc ? Is there anything else that could be causing the plugs to fail ?
Thoughts and advice please.
Cheers,
Ray
04 May 2004, 07:34 AM
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Originally Posted by Razor2001
Hi all,
1) I hear a whinning / buzzing sound coming from the rear of the car. I have no idea what it could be. It doesn't happen right away when I start the car but then in a few mins I hear it. I am pretty sure it is coming from the rear of the car and I can't hear it from the engine bay. You can hear it when car us parked in neutral and the pitch etc increases when the go peddle is pressed.
Only thing at the rear of the car are the brakes, zorst and differential correct ?
Ray
1) I hear a whinning / buzzing sound coming from the rear of the car. I have no idea what it could be. It doesn't happen right away when I start the car but then in a few mins I hear it. I am pretty sure it is coming from the rear of the car and I can't hear it from the engine bay. You can hear it when car us parked in neutral and the pitch etc increases when the go peddle is pressed.
Only thing at the rear of the car are the brakes, zorst and differential correct ?
Ray
04 May 2004, 11:21 AM
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Originally Posted by russell hayward
Fuel pump ?
Hi,
Was thinking the same thing but when I press my ear to the back seat I don't hear it that well but when I stick my head under the car I hear it very well.
Thoughts ?
Cheers,
Ray
04 May 2004, 01:15 PM
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Hi,
Ok it sounds like it could be coming from the fuel pump. Is there anyway for me to check the pump via a delta dash log or some other test ?
Any other ideas ?
Thanks again.
Cheers,
Ray
Ok it sounds like it could be coming from the fuel pump. Is there anyway for me to check the pump via a delta dash log or some other test ?
Any other ideas ?
Thanks again.
Cheers,
Ray
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04 May 2004, 05:46 PM
#8
Ecu Specialist
Deltadash will log the duty cycle being applied to the fuel pump ie 33/66/100% however it wouldn't necessarily confirm its running at that.
Does sound like the pump, they can/do get noisy. You should monitor your fuel pressure if possible.
bob
Does sound like the pump, they can/do get noisy. You should monitor your fuel pressure if possible.
bob
04 May 2004, 06:51 PM
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Hi,
Does a noisy fuel pump usually signal that it is on the way out or do they just get noisy over time but still function correctly ?
Any ideas on the hesitation ? Does it sound like the spark plugs again ?
Cheers,
Ray
Does a noisy fuel pump usually signal that it is on the way out or do they just get noisy over time but still function correctly ?
Any ideas on the hesitation ? Does it sound like the spark plugs again ?
Cheers,
Ray
04 May 2004, 09:09 PM
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Originally Posted by Andy McCord
does it make a gurguling noise on priming B4 starting?
04 May 2004, 10:27 PM
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What pump do you have in there? I had a Walbro go very noisy on me (it lead a hard life in it's early days before I fixed starvation issues...). However, changing it had no effect on the intermittent det problem I was trying to resolve at the time.
Try putting in your original pump (be careful though - what boost are you running with the remap, and at what boost/revs do you experience the problem?)? Would also be worth checking the state of the plugs - maybe the pump's been overloading the regulator, or your closed loop fuelling is way too rich due to a knackered lambda. Could be that the new plugs were gapped wrong too. But none of these things would cause a noisy pump, and if the pump got noisy at the same time as the problem appeared.......
Very hard to diagnose without seeing what the ecu is basing it's decisions on, as opposed to reality. It sounds like you have access to DDash, you just need someway of monitoring AFR's and det now, and a fuel pressure gauge would be good.
Richard
Try putting in your original pump (be careful though - what boost are you running with the remap, and at what boost/revs do you experience the problem?)? Would also be worth checking the state of the plugs - maybe the pump's been overloading the regulator, or your closed loop fuelling is way too rich due to a knackered lambda. Could be that the new plugs were gapped wrong too. But none of these things would cause a noisy pump, and if the pump got noisy at the same time as the problem appeared.......
Very hard to diagnose without seeing what the ecu is basing it's decisions on, as opposed to reality. It sounds like you have access to DDash, you just need someway of monitoring AFR's and det now, and a fuel pressure gauge would be good.
Richard
05 May 2004, 12:48 AM
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Hi Ray,
The plugs might be fouling if you have lots of short trips and the plugs don't have time to burn off deposits at their operating temps.
If you are doing lots of short trips, you could try going to a hotter plug like a "6" instead of a "7" - might help?
Not sure about the effect a hotter plug may have on det, tho' - its possible that it could increase the likelihood of DET by taking less heat out of the combustion chamber? - some others may have more knowledge of this than I... (I'm no expert!)
The plugs might be fouling if you have lots of short trips and the plugs don't have time to burn off deposits at their operating temps.
If you are doing lots of short trips, you could try going to a hotter plug like a "6" instead of a "7" - might help?
Not sure about the effect a hotter plug may have on det, tho' - its possible that it could increase the likelihood of DET by taking less heat out of the combustion chamber? - some others may have more knowledge of this than I... (I'm no expert!)
05 May 2004, 01:03 AM
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Hi guys,
I am gonna get my knock link installed and see what it shows. It's weird, sometimes I hear the noise and sometimes I don't...
Hi Bret,
The hotter plugs may be a good idea as I do have lots of short trips....I am concerned though about the det with going with a hotter plug....any pros care to comment ?
I lent a buddy my old pump....I will try and track it down....
Cheers,
Ray
I am gonna get my knock link installed and see what it shows. It's weird, sometimes I hear the noise and sometimes I don't...
Hi Bret,
The hotter plugs may be a good idea as I do have lots of short trips....I am concerned though about the det with going with a hotter plug....any pros care to comment ?
I lent a buddy my old pump....I will try and track it down....
Cheers,
Ray
05 May 2004, 02:21 PM
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Recently thought I heard det so posted some logs on here and some of the pros said that everything looked good. I will be installing a knock link in about 2 weeks (waiting for it to arrive).
06 May 2004, 12:17 AM
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Check this out...car was running smooth again today no hesitation......I have not heard the noise either ? Sound like an intermittent fuel pump issue to you all ?
Is it really neccessary to change the regulator when upgrading to the walbro fuel pump to run estimated 330 BHP ?
Oh yea and please see other questions above
Cheers,
Ray
Is it really neccessary to change the regulator when upgrading to the walbro fuel pump to run estimated 330 BHP ?
Oh yea and please see other questions above
Cheers,
Ray
08 May 2004, 03:12 PM
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Originally Posted by urban
At 4.02 in the morning, I'm not surprised Shaun
Yea, I am on a diff time zone and if you look above I sent many posts during normal hours for you dudes
Can someone read teh log and help me out please
Cheers,
Ray
11 May 2004, 02:38 AM
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I fitted the sensor on the left side of the block (looking forward) under the blow off valve. There is a free threaded hole there. You need to remove the strut brace and intercooler to get access.
Running the wiring can be a pain as the grommet (on the right where the boost guage line usually goes) are tight, but once through, I found that the knocklink box fitted really well inside the hinged pocked covering the fuse box. (below the intercooler spray switch). You can leave it closed if you want to keep the box out of sight or open it to see activity. Its a bit out of sight there though.
To get the lights more visible, I desoldered the LEDs and made up an extension cable and a mini knocklink display which I attached to the top of the steering column under the main instrument cluster. Others have moved the LEDs to the dash or to the front of the "business card" holder next to the cupholder.
Good luck.
Running the wiring can be a pain as the grommet (on the right where the boost guage line usually goes) are tight, but once through, I found that the knocklink box fitted really well inside the hinged pocked covering the fuse box. (below the intercooler spray switch). You can leave it closed if you want to keep the box out of sight or open it to see activity. Its a bit out of sight there though.
To get the lights more visible, I desoldered the LEDs and made up an extension cable and a mini knocklink display which I attached to the top of the steering column under the main instrument cluster. Others have moved the LEDs to the dash or to the front of the "business card" holder next to the cupholder.
Good luck.
11 May 2004, 08:44 PM
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Originally Posted by Razor2001
Hey thanks Bretman ! Set on max sensitivity correct ?
GRN GRN YLW YLW RED
Yep... I get one or at the most two green lights on mine. I did get a red flash once (the big light), but put it down to dodgy fuel as it hasn't occured again.
Interestingly before the remap I got two greens and sometimes one yellow at high revs, so it seems to have made a difference.