Odd running issues on new engine
Discussion
Ok, so my car's been off the road since september since blowing the HG but the garage are having trouble in getting it running again with the newly rebuilt engine. I thought i'd put some of the symptoms they're reporting in here just in case anyone has had something similar and managed to resolve, as from what i've been told, it's definitely nothing "normal" which is why they're struggling to diagnose it. Bare in mind the following is just what i've been told, but i'm desperate to get the car back 
Symptoms: Engine will start and fire up, but won't idle. All ECU diagnostics show ok, except for an intermittent "spike" in the ignition trace. The engine will run for a few seconds without throttle and then stop dead.
It can be restarted straight away, but does the same thing.
Parts tried: All normal setup (throttle pots etc) has been done. New ECU loom (run outside the car), new fuse board and relays. Disconnected the alternator and it fixed it, but now a new alternator fitted, the symptoms are back.
They had confirmed that they are sure it's something causing electrical interference with the ignition, however they seem to be relying on the ECU trace to diagnose it, yet all this shows is an "intermittent spike"... presuming in the ignition.
Next on their list is the inertia switch. But apart from that i'm not sure what the plan is.
Anyone with any other thoughts/ideas? This is a well known garage with all the right tools, so i have to presume that if they haven't fixed it after having it for a week so far, that it's not something that's common. Car is a mk2 Tuscan with the pod dash if that makes any difference.
Just want the car back and running now but there's currently no end in sight
Symptoms: Engine will start and fire up, but won't idle. All ECU diagnostics show ok, except for an intermittent "spike" in the ignition trace. The engine will run for a few seconds without throttle and then stop dead.
It can be restarted straight away, but does the same thing.
Parts tried: All normal setup (throttle pots etc) has been done. New ECU loom (run outside the car), new fuse board and relays. Disconnected the alternator and it fixed it, but now a new alternator fitted, the symptoms are back.
They had confirmed that they are sure it's something causing electrical interference with the ignition, however they seem to be relying on the ECU trace to diagnose it, yet all this shows is an "intermittent spike"... presuming in the ignition.
Next on their list is the inertia switch. But apart from that i'm not sure what the plan is.
Anyone with any other thoughts/ideas? This is a well known garage with all the right tools, so i have to presume that if they haven't fixed it after having it for a week so far, that it's not something that's common. Car is a mk2 Tuscan with the pod dash if that makes any difference.
Just want the car back and running now but there's currently no end in sight
Cheers for the quick replies.
Going on what i've been told: They've tried a different ECU, with no luck.
Walford: The injectors are all new, and i'd asked them to flow test the fuel pump as part of the rebuild (as it was running lean before). It's definitely running rich so I have to presume the fuel pressure is good.
GarryA: The battery was my first thought too. Especially as they said that disconnecting the alternator resolved it. They then fitted a new alternator and it ran ok for a bit but then started playing up again. I don't know if they tried it with the new alternator disconnected at all. (You would hope so but I can't confirm). The garage have said that they've tried another battery/ or used a battery booster pack so they're happy that it's not the cause, however my logical brain says that if mucking around with the alternator made some difference to it, then it's an issue with the overal electrics (i.e. overall power supply/charge) rather than a specific circuit.
I already have a new battery at home waiting to be fitted as the old one was struggling a little before the engine blew.
I might get them to confirm whether it still happens with the new alternator disconnected, and a new battery fitted as this would be what I would try.
I might pop the new battery up to them next week if they haven't resolved it, and run it without the alternator attached, at least for my sanity as it's what i'd do!
And I think Chad is correct, they dont run a maf sensor from my understanding (happy to be corrected though!)
Going on what i've been told: They've tried a different ECU, with no luck.
Walford: The injectors are all new, and i'd asked them to flow test the fuel pump as part of the rebuild (as it was running lean before). It's definitely running rich so I have to presume the fuel pressure is good.
GarryA: The battery was my first thought too. Especially as they said that disconnecting the alternator resolved it. They then fitted a new alternator and it ran ok for a bit but then started playing up again. I don't know if they tried it with the new alternator disconnected at all. (You would hope so but I can't confirm). The garage have said that they've tried another battery/ or used a battery booster pack so they're happy that it's not the cause, however my logical brain says that if mucking around with the alternator made some difference to it, then it's an issue with the overal electrics (i.e. overall power supply/charge) rather than a specific circuit.
I already have a new battery at home waiting to be fitted as the old one was struggling a little before the engine blew.
I might get them to confirm whether it still happens with the new alternator disconnected, and a new battery fitted as this would be what I would try.
I might pop the new battery up to them next week if they haven't resolved it, and run it without the alternator attached, at least for my sanity as it's what i'd do!
And I think Chad is correct, they dont run a maf sensor from my understanding (happy to be corrected though!)
Edited by MrChips on Sunday 22 April 15:50
Cheers Dom,
For some reason, i'd presumed the tank would have been drained as part of removing the engine, but I guess if not then crap fuel could also be the culprit. The car's been off the road since Sept so it's not going to be fresh I wouldn't normally think old fuel would make it run quite so badly as it is. I've asked them to double check anyway!
Off topic: I helped my friend buy Gary Beeton's T350 on Sat, so you'll be seeing the car again for a service soon. Your advice was spot on as the car looks perfect!
For some reason, i'd presumed the tank would have been drained as part of removing the engine, but I guess if not then crap fuel could also be the culprit. The car's been off the road since Sept so it's not going to be fresh I wouldn't normally think old fuel would make it run quite so badly as it is. I've asked them to double check anyway!
Off topic: I helped my friend buy Gary Beeton's T350 on Sat, so you'll be seeing the car again for a service soon. Your advice was spot on as the car looks perfect!
MrChips said:
Off topic: I helped my friend buy Gary Beeton's T350 on Sat, so you'll be seeing the car again for a service soon. Your advice was spot on as the car looks perfect!
I was with Gary on Saturday! I cant believe he has sold that car! He will regret it!!Good luck with the Tuscan Dave.
MrChips said:
Symptoms: Engine will start and fire up, but won't idle. All ECU diagnostics show ok, except for an intermittent "spike" in the ignition trace. The engine will run for a few seconds without throttle and then stop dead.
It can be restarted straight away, but does the same thing.
Mine started doing exactly the same, starting but not idling for long before the revs reduced until it stopped, as soon as I tried to give any revs at all it would also stop. After a few minutes of restarting there seems to be enough heat generated to allow it to run. Also when ambient temp is above 12 or 13 degrees she starts and idles without an issue. So with mine at least I'm pretty sure it is somehow temperature related. It can be restarted straight away, but does the same thing.
From what i've been told, it was a feed wire to the ECU that was corroded, no more info on what feed etc but hopefully it's fixed.
Only issue now is that the dash pod display is either going mental with the display all scrambled, or not displaying at all. Hopefully it's a loose connection although not ideal to have the car back without it being sorted
On a positive note, the new ACT cans sound great with the decat. Not ventured above 3k rpm yet but looking forward to it!
Only issue now is that the dash pod display is either going mental with the display all scrambled, or not displaying at all. Hopefully it's a loose connection although not ideal to have the car back without it being sorted
On a positive note, the new ACT cans sound great with the decat. Not ventured above 3k rpm yet but looking forward to it!
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