won't start when hot
#16
07-08-2014, 01:16 PM
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Location: Scotland
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#17
07-17-2014, 12:39 PM
Join Date: Oct 2011
Location: Thornhill, Ontario CANADA
Posts: 539
Rep Power: 47
I have ordered both fuel pump relays and the starter motor relay. These are inexpensive pieces and provide a good starting (no pun intended) point. I'll report back
#19
07-18-2014, 07:45 AM
Join Date: Oct 2011
Location: Thornhill, Ontario CANADA
Posts: 539
Rep Power: 47
Condition only occurs under unique circumstances: high heat/humidity after sitting in sun for 2 1/2 hours. Consequently, I haven't been able to replicate conditions. No error codes at this point. I keep waiting for environment to be right. In the meantime, car performs perfectly. Once I replace the relays, I'll take the old ones apart and see if I can discover anything untoward. I'll come back with any news.
#20
07-29-2014, 11:39 AM
Join Date: Oct 2011
Location: Thornhill, Ontario CANADA
Posts: 539
Rep Power: 47
Today I changed the fuel filter and replaced both fuel pump relays and the starter relay. Now, I'll try road-testing to see if problem is still present under extreme conditions. It is worth noting that no fault codes exist either before or after the relay/fuel filter replacements.
#21
08-01-2014, 01:46 PM
Join Date: Oct 2011
Location: Thornhill, Ontario CANADA
Posts: 539
Rep Power: 47
Update: finally got a day suitable for testing. i.e. Hot and Humid. Drove car for 40 minutes. Parked it in the sun for two hours. It started. Drove it around the block and let it sit in the sun for another 30 minutes. It WOULDN'T start. Left it for 35 minutes and it started. Upon start, idle was rough and smoothed out after 15 seconds. Shut car down and restarted it immediately. Idle was smooth. I suspect fuel pump pressure issue. I'll report back, but welcome any insights you guys might have.
#23
08-29-2014, 01:59 PM
Join Date: Oct 2011
Location: Thornhill, Ontario CANADA
Posts: 539
Rep Power: 47 
OK..three weeks of investigation (seriously) have yielded the following: Fuel pressures were good. In fact, everything checked out to be in spec. However, the harness on bank 1 (passenger side for lhd) had a cracked wire. We were finally able to replicate the problem by wiggling the harness just below the connector to the computer module under the cowl. We redid the connector pins and thought we had it, but the problem remained. We then went further down the harness (toward the engine) and discovered a cracked wire casing. Further investigation revealed that two of the four filaments we're broken. We put in a new section of wire (complete with heat shrink) and voila, the problem went away (so far). The car now is absolutely smooth at 500 rpm and the engine seems to make more power from the turbos. It is worth noting that when the no-start condition existed, the idle had become slightly rough and the DTCs showed bank one too rich and occasional CEL on and off. We have tested the car for three days now and are unable to create the hot no-start condition. Fingers crossed.
It is said, that with enough patience and perseverance, one can fornicate with a spider.
It is said, that with enough patience and perseverance, one can fornicate with a spider.
Last edited by PMS; 08-29-2014 at 02:03 PM. Reason: expansionn
#24
08-29-2014, 02:38 PM
Registered User
Join Date: May 2010
Location: Scotland
Posts: 1,454
Rep Power: 95 OK..three weeks of investigation (seriously) have yielded the following: Fuel pressures were good. In fact, everything checked out to be in spec. However, the harness on bank 1 (passenger side for lhd) had a cracked wire. We were finally able to replicate the problem by wiggling the harness just below the connector to the computer module under the cowl. We redid the connector pins and thought we had it, but the problem remained. We then went further down the harness (toward the engine) and discovered a cracked wire casing. Further investigation revealed that two of the four filaments we're broken. We put in a new section of wire (complete with heat shrink) and voila, the problem went away (so far). The car now is absolutely smooth at 500 rpm and the engine seems to make more power from the turbos. It is worth noting that when the no-start condition existed, the idle had become slightly rough and the DTCs showed bank one too rich and occasional CEL on and off. We have tested the car for three days now and are unable to create the hot no-start condition. Fingers crossed.
It is said, that with enough patience and perseverance, one can fornicate with a spider.
It is said, that with enough patience and perseverance, one can fornicate with a spider.
Good News.....keep us all informed on how it goes.
#25
10-24-2014, 06:10 AM
OK..three weeks of investigation (seriously) have yielded the following: Fuel pressures were good. In fact, everything checked out to be in spec. However, the harness on bank 1 (passenger side for lhd) had a cracked wire. We were finally able to replicate the problem by wiggling the harness just below the connector to the computer module under the cowl. We redid the connector pins and thought we had it, but the problem remained. We then went further down the harness (toward the engine) and discovered a cracked wire casing. Further investigation revealed that two of the four filaments we're broken. We put in a new section of wire (complete with heat shrink) and voila, the problem went away (so far). The car now is absolutely smooth at 500 rpm and the engine seems to make more power from the turbos. It is worth noting that when the no-start condition existed, the idle had become slightly rough and the DTCs showed bank one too rich and occasional CEL on and off. We have tested the car for three days now and are unable to create the hot no-start condition. Fingers crossed.
It is said, that with enough patience and perseverance, one can fornicate with a spider.
It is said, that with enough patience and perseverance, one can fornicate with a spider.
I have the same problem. But I need detailed instructions on which wiring casings where cracked and exactly where you found these to be. Also what colour where the wires. I would be obliged if you could provide the details for this fix please. Thanks.
Last edited by Johnny Hotspur GT; 09-29-2021 at 02:55 PM. Reason: Fix QUOTE
#26
10-24-2014, 09:31 AM
Join Date: Oct 2011
Location: Thornhill, Ontario CANADA
Posts: 539
Rep Power: 47
Anush,
Rather than reply to your PM, I have elected to share my experience with all forum members. Hopefully others will join in on this dialogue and make further contribution.
I am assuming you have read this thread thoroughly and have checked all the possible areas (e.g. ground wire to the starter, KESSY under the floor, relays, fuel pressures, etc.)
One step I don't think I revealed was that we were getting an intermittent crank shaft sensor error. We replaced the sensor before tackling the wiring.
It is worth noting that with my car, if we left it idling for 20-25 minutes, it would quit which indicated a heat-soak condition.
The condition was extremely hard to replicate using only environmental considerations (i.e. high ambient temperature with high humidity). Once we discovered wiggling the connectors, we could induce the hot-no-start condition repeatedly.
Here's what I recommend:
1. Again assuming you have a DTC error on bank 1 (with my car, the error was rich on bank 1). With the car running, wiggle the connector to the ecu under the cowl on the passenger side (LHD car). Does the car stop?
2. If "yes", check the pins to the connector. Ensure they are tight and not broken.
3. If the pins are OK, check two wires. Yellow and blue/white. We had breaks in both. One goes to the fuse panel and one goes to the engine. I can't remember which is which.
Please let us know how you are making out. If you need more info, I am happy to help.
Rather than reply to your PM, I have elected to share my experience with all forum members. Hopefully others will join in on this dialogue and make further contribution.
I am assuming you have read this thread thoroughly and have checked all the possible areas (e.g. ground wire to the starter, KESSY under the floor, relays, fuel pressures, etc.)
One step I don't think I revealed was that we were getting an intermittent crank shaft sensor error. We replaced the sensor before tackling the wiring.
It is worth noting that with my car, if we left it idling for 20-25 minutes, it would quit which indicated a heat-soak condition.
The condition was extremely hard to replicate using only environmental considerations (i.e. high ambient temperature with high humidity). Once we discovered wiggling the connectors, we could induce the hot-no-start condition repeatedly.
Here's what I recommend:
1. Again assuming you have a DTC error on bank 1 (with my car, the error was rich on bank 1). With the car running, wiggle the connector to the ecu under the cowl on the passenger side (LHD car). Does the car stop?
2. If "yes", check the pins to the connector. Ensure they are tight and not broken.
3. If the pins are OK, check two wires. Yellow and blue/white. We had breaks in both. One goes to the fuse panel and one goes to the engine. I can't remember which is which.
Please let us know how you are making out. If you need more info, I am happy to help.
#27
09-29-2021, 02:57 PM
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