Turbo'd 24erty4er
Member
- Joined
- Oct 22, 2004
- Location
- Vancouver,B.C., Canada
Having intermittent rough running - invariably when the vehicle has been brought up to operating temperature and then not driving it for approximately 30 minutes. It varies of course but when it does occur there is cutting out ,as well as an increase in fuel as it can be smelled and difficulty accelerating from rest, in fact it tends to not respond and barely moves and when coaxed will buck and as mentioned, cutting out as it slowly clears and eventually runs more or less evenly.
The car will also stall readily as it approaches idle as well. Never a problem when cold and up until recently ran quite smoothly. There have been a few modifications such as a chipped ECU and EZK, green top injectors, 3" MAF, 16T turbo, KL Racing inter cooler and IPD cam but it always ran very well.
At times it can feel a bit "off " when driving and there can be a bit of roughness detected and a reduction in response and it will invariably act up once shut off and restarted after those 20 - 40 minutes.
So far I have not tried to check for any OBD codes, replaced the ECU temperature sensor, recently swapped the FPR with a known good unit but have yet to drive the car. I have a second '94 945T I removed it from, just swapped them and the donor 945 ran fine though not all that far so difficult to say. Thinking it just might be the main fuel pump, the in tank was replaced in the last 3-4 years, new cap, rotor and plugs/ wires and as mentioned when it is running issue free it is quite good.
I have not tested the fuel rest or line pressure as I do not have a gauge etc. but thought of trying a spare used Bosch oem fuel pump I have on hand but really do not want to bother if it is not the problem, plus I have had that pump for a few years, Perhaps I should just buy a new one just to know it is done as I have no idea how long the original has been in the car. Should also mention there is a recent fuel pump relay, even tried a spare while on a trip recently when it acted up and no change. Have checked grounding points and in fact am in the process of applying Ox Gard at all electrical connections, have used Deox it previously on the various connectors on the engine. Had a spare injector relay as well when it was doing its thing and it finally ran albeit not all that well but it did so that could just be a fluke. Can that relay simply get too warm and go intermittent? I would think they would either work or not.
It seems to me that perhaps the main fuel pump is showing signs of wear as this can result in unpredictable fuel problems, though doing so when warm is perhaps a bit puzzling. The Beck / Arnley FPRs seem to be good quality for a reasonable cost from RockAuto but if I find the problem persists with a good FPR no point in ordering one.
I also noticed the car has become rough feeling, the tires are coming up on 8 years and definitely becoming noisy and I think the centre support and/or bearing is starting to show its age as well so the combination is such that highway driving has become rather tiresome. I feel removing the driveshaft and having it checked ( u joints and balancing ) might be a good idea. The car is lowered 40 mm on progressive springs and currently have a BNE adjustable panhard rod and would like to put their adjustable torque rods in as well to get the pinion angle where it should be.
The driveshaft can make allowances apparently but a binding or loose u joint can cause difficulties - all the suspension bushings have been replaced with Super Pro poly, front and back and the rear sub frame reinforced.
The car is stiff with Bilstein HD shocks but was always at least manageable until the above noise issues started. Just hope to address them before too long!
The car will also stall readily as it approaches idle as well. Never a problem when cold and up until recently ran quite smoothly. There have been a few modifications such as a chipped ECU and EZK, green top injectors, 3" MAF, 16T turbo, KL Racing inter cooler and IPD cam but it always ran very well.
At times it can feel a bit "off " when driving and there can be a bit of roughness detected and a reduction in response and it will invariably act up once shut off and restarted after those 20 - 40 minutes.
So far I have not tried to check for any OBD codes, replaced the ECU temperature sensor, recently swapped the FPR with a known good unit but have yet to drive the car. I have a second '94 945T I removed it from, just swapped them and the donor 945 ran fine though not all that far so difficult to say. Thinking it just might be the main fuel pump, the in tank was replaced in the last 3-4 years, new cap, rotor and plugs/ wires and as mentioned when it is running issue free it is quite good.
I have not tested the fuel rest or line pressure as I do not have a gauge etc. but thought of trying a spare used Bosch oem fuel pump I have on hand but really do not want to bother if it is not the problem, plus I have had that pump for a few years, Perhaps I should just buy a new one just to know it is done as I have no idea how long the original has been in the car. Should also mention there is a recent fuel pump relay, even tried a spare while on a trip recently when it acted up and no change. Have checked grounding points and in fact am in the process of applying Ox Gard at all electrical connections, have used Deox it previously on the various connectors on the engine. Had a spare injector relay as well when it was doing its thing and it finally ran albeit not all that well but it did so that could just be a fluke. Can that relay simply get too warm and go intermittent? I would think they would either work or not.
It seems to me that perhaps the main fuel pump is showing signs of wear as this can result in unpredictable fuel problems, though doing so when warm is perhaps a bit puzzling. The Beck / Arnley FPRs seem to be good quality for a reasonable cost from RockAuto but if I find the problem persists with a good FPR no point in ordering one.
I also noticed the car has become rough feeling, the tires are coming up on 8 years and definitely becoming noisy and I think the centre support and/or bearing is starting to show its age as well so the combination is such that highway driving has become rather tiresome. I feel removing the driveshaft and having it checked ( u joints and balancing ) might be a good idea. The car is lowered 40 mm on progressive springs and currently have a BNE adjustable panhard rod and would like to put their adjustable torque rods in as well to get the pinion angle where it should be.
The driveshaft can make allowances apparently but a binding or loose u joint can cause difficulties - all the suspension bushings have been replaced with Super Pro poly, front and back and the rear sub frame reinforced.
The car is stiff with Bilstein HD shocks but was always at least manageable until the above noise issues started. Just hope to address them before too long!
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