Discussion
You've obviously done a lot of investigation and I haven't followed up all the previous suggestions. Have you been able to rule out any of these areas? If so, how; if not, what have you tried so far in each area?
- a mechanical problem (pistons, valve train, blocked exhaust etc)
- a fuel system problem
- an ignition problem
Hi all, a quick update having received the STAR tester from Philpot...
The random high idle with the ISCV plugged in seems to have made a resurgence today, so we weren't able to complete all the tests however:
- with the key on-engine off test, we got a code 11 - no fault found. I head various solenoids clicking etc which I don't think I had heard on other testers, so had a bit more confidence that it was doing the business. Interestingly it doesn't return a fault code (46) with the ISCV unplugged, so suspect this is only checked as part of the dynamic engine running tests. Unplugging the TPS correctly generated a code 35, so gave a degree of confidence in the system.
- For the key on engine running test with ISCV unplugged, we correctly got a 46, (ISCV failure). Plugging it in with the engine maintaining around 2000 rpm (symptomatic of the long-standing idle issue) we got a code 16 ("Vane air meter number 2"), for which it says to "check base idle speed". The engine then cuts out as the ECU seemingly tries to conduct more dynamic engine tests. Thinking positively, the STAR tester is at least identifying that things ain't right, we now just need to work out why!
Despite recently changing the intake plenum gasket, our thinking is that it might indicate that an excessive amount of air is still being sucked in from somewhere. A number of you have said that ignition shouldn't be sustainable with the ISCV unplugged, and for the majority of time it is, so the next plan is to work out why that is. I'm gonna try get my hands on a smoke tester to flush out where any leaks might be.
As far as these go:
a mechanical problem (pistons, valve train, blocked exhaust etc) - nope, these are a bit out of my ability to check, so I haven't done them. We'll look at them post air leak checks
a fuel system problem - difficult to confirm 100% that there isn't an issue, but having replaced filters, injectors, fuel pressure regulator and confirmed the fuel pressure looks to be in limits, I'm hoping it is sorted.
an ignition problem - we have replaced pretty much everything in the ignition system and it gives a very good spark, so not likely to be ignition.
The random high idle with the ISCV plugged in seems to have made a resurgence today, so we weren't able to complete all the tests however:
- with the key on-engine off test, we got a code 11 - no fault found. I head various solenoids clicking etc which I don't think I had heard on other testers, so had a bit more confidence that it was doing the business. Interestingly it doesn't return a fault code (46) with the ISCV unplugged, so suspect this is only checked as part of the dynamic engine running tests. Unplugging the TPS correctly generated a code 35, so gave a degree of confidence in the system.
- For the key on engine running test with ISCV unplugged, we correctly got a 46, (ISCV failure). Plugging it in with the engine maintaining around 2000 rpm (symptomatic of the long-standing idle issue) we got a code 16 ("Vane air meter number 2"), for which it says to "check base idle speed". The engine then cuts out as the ECU seemingly tries to conduct more dynamic engine tests. Thinking positively, the STAR tester is at least identifying that things ain't right, we now just need to work out why!
Despite recently changing the intake plenum gasket, our thinking is that it might indicate that an excessive amount of air is still being sucked in from somewhere. A number of you have said that ignition shouldn't be sustainable with the ISCV unplugged, and for the majority of time it is, so the next plan is to work out why that is. I'm gonna try get my hands on a smoke tester to flush out where any leaks might be.
As far as these go:
a mechanical problem (pistons, valve train, blocked exhaust etc) - nope, these are a bit out of my ability to check, so I haven't done them. We'll look at them post air leak checks
a fuel system problem - difficult to confirm 100% that there isn't an issue, but having replaced filters, injectors, fuel pressure regulator and confirmed the fuel pressure looks to be in limits, I'm hoping it is sorted.
an ignition problem - we have replaced pretty much everything in the ignition system and it gives a very good spark, so not likely to be ignition.
Well the search continues...
I acquired a smoke machine (one of the cheap Autool ones of eBay which actually seem to work pretty well!) and disappointingly it didn't reveal the panacea air leak that we were hoping. We plugged the machine into air sources (brake servo hose, intake, plenum hose) and there weren't any great leaks on engine side of the throttle body. There is definitely a small leak out of the throttle body spindle, so Lee has cleaned up the spare which seals better. There was also air leaking in around the intake hoses so currently trying to source some new ones, as never been a fan of the sprung-steel reinforced type ones.
It is at least reassuring that Lee's work in replacing the plenum and fuel rail gaskets has got it all sealed up tightly, but we were hoping that we saw massive Indian smoke signals pointing to where the problem might lie! We'll get the throttle body and the hoses sealed up properly and then re-run the smoke test and STAR tests and put the thinking cap back on!
I acquired a smoke machine (one of the cheap Autool ones of eBay which actually seem to work pretty well!) and disappointingly it didn't reveal the panacea air leak that we were hoping. We plugged the machine into air sources (brake servo hose, intake, plenum hose) and there weren't any great leaks on engine side of the throttle body. There is definitely a small leak out of the throttle body spindle, so Lee has cleaned up the spare which seals better. There was also air leaking in around the intake hoses so currently trying to source some new ones, as never been a fan of the sprung-steel reinforced type ones.
It is at least reassuring that Lee's work in replacing the plenum and fuel rail gaskets has got it all sealed up tightly, but we were hoping that we saw massive Indian smoke signals pointing to where the problem might lie! We'll get the throttle body and the hoses sealed up properly and then re-run the smoke test and STAR tests and put the thinking cap back on!
ukflyboy said:
Well the search continues...
I acquired a smoke machine (one of the cheap Autool ones of eBay which actually seem to work pretty well!) and disappointingly it didn't reveal the panacea air leak that we were hoping. We plugged the machine into air sources (brake servo hose, intake, plenum hose) and there weren't any great leaks on engine side of the throttle body. There is definitely a small leak out of the throttle body spindle, so Lee has cleaned up the spare which seals better. There was also air leaking in around the intake hoses so currently trying to source some new ones, as never been a fan of the sprung-steel reinforced type ones.
It is at least reassuring that Lee's work in replacing the plenum and fuel rail gaskets has got it all sealed up tightly, but we were hoping that we saw massive Indian smoke signals pointing to where the problem might lie! We'll get the throttle body and the hoses sealed up properly and then re-run the smoke test and STAR tests and put the thinking cap back on!
I have only just read all of this thread and OP i admire your determination.I acquired a smoke machine (one of the cheap Autool ones of eBay which actually seem to work pretty well!) and disappointingly it didn't reveal the panacea air leak that we were hoping. We plugged the machine into air sources (brake servo hose, intake, plenum hose) and there weren't any great leaks on engine side of the throttle body. There is definitely a small leak out of the throttle body spindle, so Lee has cleaned up the spare which seals better. There was also air leaking in around the intake hoses so currently trying to source some new ones, as never been a fan of the sprung-steel reinforced type ones.
It is at least reassuring that Lee's work in replacing the plenum and fuel rail gaskets has got it all sealed up tightly, but we were hoping that we saw massive Indian smoke signals pointing to where the problem might lie! We'll get the throttle body and the hoses sealed up properly and then re-run the smoke test and STAR tests and put the thinking cap back on!
You obviously have an intermittent fault, and for my twopenny worth it sounds as though it sometimes is overfuelling.
You say you have checked the temp sensor, for what its worth i would buy a new one.
Theres not much you havnt done or replaced, but some kind of overfueling problem is my guess....................it is only a guess
though, but having read all of this thread quite a few times, it seems a good possibility.
Thanks Tom, unfortunately I don't have much choice but to be persistent with it; I can't find any professional that sounds like they might know how to solve it so the only other option is to sell it as a going concern which I don't want to do given the work that has been done on it - I'm determined to believe that I'll have years of great running with it once I can get this sorted!
There is a definitely possibility of overfuelling but it won't be due to the temp sensor - I've tested the one that was in there and a new one with an ohm metre across a variety of temperatures and they were operating correctly (checked back at the ECU also).
It's a real head-scratcher!
There is a definitely possibility of overfuelling but it won't be due to the temp sensor - I've tested the one that was in there and a new one with an ohm metre across a variety of temperatures and they were operating correctly (checked back at the ECU also).
It's a real head-scratcher!
I know they are no where near but they are very knowledgeable around old school fords - the amount of time this has been going on it could be worth a trip.
They were a non franchised ford dealer for quite some time in the 90's.
Steve who runs the workshop fixed a local TVR S not so long back that wouldn't idle - it was a break in the wiring to the idle control valve.
It didn't take them long to find it.
https://www.wilfordlaneautos.co.uk/
Chris
They were a non franchised ford dealer for quite some time in the 90's.
Steve who runs the workshop fixed a local TVR S not so long back that wouldn't idle - it was a break in the wiring to the idle control valve.
It didn't take them long to find it.
https://www.wilfordlaneautos.co.uk/
Chris
Have you checked the ball valve ( is it called that?) on the rockercover and the valve sitting next to it and turned the right way (same hose loop)?
Do the non cat 2.9 the butterfly valves in the air intake? If it have they can get sticky.
Maybe already checked the idle engine vale?
Cleaned and checked that the filter in the oil filling cap + hose working as it should (crankcase breather?)
Do the non cat 2.9 the butterfly valves in the air intake? If it have they can get sticky.
Maybe already checked the idle engine vale?
Cleaned and checked that the filter in the oil filling cap + hose working as it should (crankcase breather?)
Edited by Maffe on Saturday 27th October 18:14
Edited by Maffe on Saturday 27th October 18:19
It sounds as though you have tried pretty much everything. Intermittent wiring faults are obviously a b**g*r to find as broken conductors or poor connections can still make contact even during wiggle tests, only to go open circuit 5 minutes later..
Two small suggestions I didn’t notice specifically mentioned in your thread, but which you may well have tried already,
1) Try cleaning up all the pins in the small round multi-pin connector in the V of the engine which connects the sensors to the ECU (on my car it is hidden under the coil) it lives in a pretty harsh environment and is very subject to corrosion, which might distort the signals to the ECU.
2) try actually driving the car with the TPS unplugged. It will not run well but if it loses the rough running in limp home mode maybe the fault could be in the wiring to the TPS rather than in the TPS itself (I see you have already tried a new one of those).
Congratulations on your perseverance, good luck
Two small suggestions I didn’t notice specifically mentioned in your thread, but which you may well have tried already,
1) Try cleaning up all the pins in the small round multi-pin connector in the V of the engine which connects the sensors to the ECU (on my car it is hidden under the coil) it lives in a pretty harsh environment and is very subject to corrosion, which might distort the signals to the ECU.
2) try actually driving the car with the TPS unplugged. It will not run well but if it loses the rough running in limp home mode maybe the fault could be in the wiring to the TPS rather than in the TPS itself (I see you have already tried a new one of those).
Congratulations on your perseverance, good luck
Thanks for the continued suggestions here folks, I was out of the country for a bit, so diagnostics were slowed a little. Looks like we might have made some progress today; Lee had already replaced the valley gasket while I was away and we had tried just about everything except the ECU.
I sent it off to ATP Electronics to have it refurbished who noted that it had a fault in the idle channel. We refitted it today and it certainly seems to have made a huge difference - even with it only 3 odd degrees outside it starts first time every time and sits at a reasonable 900- 1000 ish RPM. We ran all the STAR diagnostics tests and it completes all of them, controlling RPM as it should in the dynamic tests and returning a beautiful code 11 (no faults found) every time! It's 6 months past its MOT so the only thing left to do is get it to a garage to fine tune the mixture (we've had AFMs in/out and cleaned), get the gearbox oil changed, throw it into an MOT and then see how it does on the road!
Will report back over the coming weeks, but looks like persistence might have paid here; I'll reserve the rest of my excitement until it has done more time on the road wheels turning than it has on a recovery truck though!
I sent it off to ATP Electronics to have it refurbished who noted that it had a fault in the idle channel. We refitted it today and it certainly seems to have made a huge difference - even with it only 3 odd degrees outside it starts first time every time and sits at a reasonable 900- 1000 ish RPM. We ran all the STAR diagnostics tests and it completes all of them, controlling RPM as it should in the dynamic tests and returning a beautiful code 11 (no faults found) every time! It's 6 months past its MOT so the only thing left to do is get it to a garage to fine tune the mixture (we've had AFMs in/out and cleaned), get the gearbox oil changed, throw it into an MOT and then see how it does on the road!
Will report back over the coming weeks, but looks like persistence might have paid here; I'll reserve the rest of my excitement until it has done more time on the road wheels turning than it has on a recovery truck though!
Things are looking positive... took for it's MOT the other day and it seems went through that with the exhaust mounts being the only advisory; turned out to be more than advisory, as by the time I'd got the 1 mile back to Lee's they had broken and had the exhaust dragging on the ground a bit! It also felt a bit flat when I put the foot down.
So I was back at Lee's on Friday and we put new exhaust mounts on, adjusted the timing to a precise 12deg BDTC and had a bit of a fiddle with the mixture and it ran about as well as it has ever run in my possession! All that is left is to pick it up this weekend and get driving it!
So I was back at Lee's on Friday and we put new exhaust mounts on, adjusted the timing to a precise 12deg BDTC and had a bit of a fiddle with the mixture and it ran about as well as it has ever run in my possession! All that is left is to pick it up this weekend and get driving it!
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