Griff 500 - Undrivable misfire in heavy rain - SOLVED
Discussion
Hello all
I've had my Griff for nearly 10 years now and suffered hardly any breakdowns. However, when it began kangerooing horribly yesterday in torrential rain and flooded roads it suddenly occurred that every time it's been on a low loader has been in similar conditions - in Slovenija, Provence and Le Mans and each time with massively flooded motorways.
Over the years I've changed fuel regulators, distributors, cam, induction and a few other components but now wonder if it was simply drying out that cured the issue each time!
Right now the car is undrivably bad. The symptoms are an increasing shunting on constant throttle that in 5 seconds gets to the point where the car feels like it's going to shake itself to bits. It will smooth out when accelerating (including if the road runs up an incline and requires throttle application to maintain speed) or on the over-run. Plugs show over fuelling, Magnecore ignition leads seem good. When working the engine is exceptionally strong but does have some low speed shunting in common with many other cars.
My guess is that either a sensor is causing the ECU to attempt to correct a non-existent issue and putting it into a quickly worsening loop, or there is another very hidden loom problem that only shows itself in extreme wet.
I've read every shunting thread on here but couldn't find any that pertain as closely to wet conditions as mine. Has anybody experienced the same or are there any simple tests I can do whilst it is not working that could point me or a specialist in the right direction?
My worry is that by the time I get it transported somewhere it could have dried out and the fault disappear!
Many thanks in advance for your help!
I've had my Griff for nearly 10 years now and suffered hardly any breakdowns. However, when it began kangerooing horribly yesterday in torrential rain and flooded roads it suddenly occurred that every time it's been on a low loader has been in similar conditions - in Slovenija, Provence and Le Mans and each time with massively flooded motorways.
Over the years I've changed fuel regulators, distributors, cam, induction and a few other components but now wonder if it was simply drying out that cured the issue each time!
Right now the car is undrivably bad. The symptoms are an increasing shunting on constant throttle that in 5 seconds gets to the point where the car feels like it's going to shake itself to bits. It will smooth out when accelerating (including if the road runs up an incline and requires throttle application to maintain speed) or on the over-run. Plugs show over fuelling, Magnecore ignition leads seem good. When working the engine is exceptionally strong but does have some low speed shunting in common with many other cars.
My guess is that either a sensor is causing the ECU to attempt to correct a non-existent issue and putting it into a quickly worsening loop, or there is another very hidden loom problem that only shows itself in extreme wet.
I've read every shunting thread on here but couldn't find any that pertain as closely to wet conditions as mine. Has anybody experienced the same or are there any simple tests I can do whilst it is not working that could point me or a specialist in the right direction?
My worry is that by the time I get it transported somewhere it could have dried out and the fault disappear!
Many thanks in advance for your help!
If you have had the induction system replaced with a K&N akin system and got rid of the thick oilly foam from the original system at the very front nose tip, then it is probably water up your induction system, and when it gets to the Air Flow meter that is when your problems will start. Very very heavy rain and stupid amounts of spray? Did your MIL light come on?
Thanks Reeso - I have no MIL lights but an interesting theory that I hadn't considered and I do have the ACT induction kit with the K&N panel filter fitted.
I'm not sure though because the car still won't drive now in bone dry conditions and I wonder whether the filter could retain enough water to still be contaminating the MAF a day later? I could always pull the filter out and try but it's such a hateful job.
In other news - lambda probes tested and both switching from zero-ish to 1v-ish every second and it runs the same with the stepper motor unplugged so that's two things to rule out!
I'm not sure though because the car still won't drive now in bone dry conditions and I wonder whether the filter could retain enough water to still be contaminating the MAF a day later? I could always pull the filter out and try but it's such a hateful job.
In other news - lambda probes tested and both switching from zero-ish to 1v-ish every second and it runs the same with the stepper motor unplugged so that's two things to rule out!
Edited by dumbfunk on Monday 13th June 12:28
Reeso said:
If you have had the induction system replaced with a K&N akin system and got rid of the thick oilly foam from the original system at the very front nose tip, then it is probably water up your induction system, and when it gets to the Air Flow meter that is when your problems will start. Very very heavy rain and stupid amounts of spray? Did your MIL light come on?
+1Hot-wire is situated in a trench in the bottom of AFM and it fills with water, one of the reasons I junked it . . . . Used to happen to mine, although the shunting wasn't quite so bad, but 8 mpg was the norm and for BB and Barretti following me it was like driving through a fuel storm on the the then new auotroute to LM without petrol stations, where inevitably it ended with them having to go and collect fuel for me, bless em.
Next time it happens, whip off the induction and I'm sure you'll find the trench and therefore hot-wire sitting in a pool of water.
If you can get your ECU fault codes it will confirm (I suspect) what we are saying. The kangerooing/lack of power etc is because the egine has shut down into a safe mode. If you disconnect the ECU for a while, dry out the AFM, put it back together it will probably sort the problem. Other than putting that large piece of oily foam back into the filter pannel, you will always have this problem in monsoon conditions. IMO!
You should also check that all your HT leads are connected to the dizzy as the violent shunting can dislodge them ;-) V6 or less anyone?!!!!
Good luck
You should also check that all your HT leads are connected to the dizzy as the violent shunting can dislodge them ;-) V6 or less anyone?!!!!
Good luck
Edited by Reeso on Monday 13th June 13:39
OK - I may owe some beers here ...
Just disconnected the MAF and about a cup of water dropped out of it as I lifted it from the car.
I'm guessing this isn't a good thing!
I'll let it dry out and retry it in an hour.
Does this mean the flat K&N filters are a waste of time? Despite a ten year PH addiction it's the first time I've heard of this problem here. If this fixes it I'll drop Tim @ ACT a note and see if he has heard of it and/or has a solution and report back.
Do I assume you guys went back to the oily sponge version?
Thanks again!
Just disconnected the MAF and about a cup of water dropped out of it as I lifted it from the car.
I'm guessing this isn't a good thing!
I'll let it dry out and retry it in an hour.
Does this mean the flat K&N filters are a waste of time? Despite a ten year PH addiction it's the first time I've heard of this problem here. If this fixes it I'll drop Tim @ ACT a note and see if he has heard of it and/or has a solution and report back.
Do I assume you guys went back to the oily sponge version?
Thanks again!
For a quick sanity check I just called Dulford as they service the car and they'd never heard of the problem with the Pipercross filters they stock which they describe as a foam rather than paper design.
In fairness my filter has been on the car for some years and never fitted particularly well perhaps due to "individualism" in my air box so that may worsen the effect. Also I guess a tiny percentage of us drive these cars in monsoon conditions and even in my case the current filter has statistically worked perfectly more than 99% of the time!
Perhaps if they're oiled regularly (mine was not I'm afraid) and proper care is take to seal the filter within the airbox there's no issue?
Anyway, road testing now, new filter on order, more news as it happens ...
In fairness my filter has been on the car for some years and never fitted particularly well perhaps due to "individualism" in my air box so that may worsen the effect. Also I guess a tiny percentage of us drive these cars in monsoon conditions and even in my case the current filter has statistically worked perfectly more than 99% of the time!
Perhaps if they're oiled regularly (mine was not I'm afraid) and proper care is take to seal the filter within the airbox there's no issue?
Anyway, road testing now, new filter on order, more news as it happens ...
Results so far - erm, inconclusive right now.
Dried the MAF out best I could and refitted. On the first test drive it's just as bad. Disconnected the air intake hose so it's sucking nasty hot (but dry!) air rather than through the filter and it's approximately 25% better.
Probably needs to dry out more ... I'll be back.
Dried the MAF out best I could and refitted. On the first test drive it's just as bad. Disconnected the air intake hose so it's sucking nasty hot (but dry!) air rather than through the filter and it's approximately 25% better.
Probably needs to dry out more ... I'll be back.
Reset ecu and make sure afm is fully dry .....
Also worth checking the carbon canister intake hose is not also running in a gully or area where it can suck up water, sometimes get positioned for neatness and the end up sucking up water when the valve is activated, then when the system operates the petrol enriched air that should be vented thru the intake system is rather a water and petrol version which buggers the running as well . . . Located osf wing . .
Also worth checking the carbon canister intake hose is not also running in a gully or area where it can suck up water, sometimes get positioned for neatness and the end up sucking up water when the valve is activated, then when the system operates the petrol enriched air that should be vented thru the intake system is rather a water and petrol version which buggers the running as well . . . Located osf wing . .
I had exactly the same issue with mine a while back. Whenever it rained it had a massive misfires issue that caused the car violently jolt several times and then cut out. The car would refuse to restart, until cooled down. Having never experienced a 5.0 rover V8 misfire I was quite shocked that the car would shake you so hard that it felt like your internal organs had been re-arranged!
My issue turned out to be a hairline crack in the dizzy cap which let moisture in. In short whenever it rained moisture could get into the dizzy coupled with the hot air being blown over the ignition system when the rad fans kicked in.
I am glad I sorted mine out as I would have probably got rid of the car if not. Where mine kept misfiring a managed to spin the car a few times as when the car was about to cut out I would try and prevent it from doing so my increasing the throttle, some times it would work and others not. There were a couple of times however that I increased the throttle and the engine burst back into life..... rainy day too much throttle
My issue turned out to be a hairline crack in the dizzy cap which let moisture in. In short whenever it rained moisture could get into the dizzy coupled with the hot air being blown over the ignition system when the rad fans kicked in.
I am glad I sorted mine out as I would have probably got rid of the car if not. Where mine kept misfiring a managed to spin the car a few times as when the car was about to cut out I would try and prevent it from doing so my increasing the throttle, some times it would work and others not. There were a couple of times however that I increased the throttle and the engine burst back into life..... rainy day too much throttle
Thanks all
@ Mpoxon - I already had this problem when a previous specialist (Not Dulford) chose to badly glue up a crack in my distributor cap rather than spend the tenner to replace it after a £2k+ major service and cam swap. Yeah, thanks for that.
Resetting ECU and retesting now. Will check the carbon can too.
...
OK - so car is now about 50% better. Shunting still pretty bad but at least driveable however the car won't take full throttle as it feels like it's holding back. I'll try again tomorrow and report back.
@ Mpoxon - I already had this problem when a previous specialist (Not Dulford) chose to badly glue up a crack in my distributor cap rather than spend the tenner to replace it after a £2k+ major service and cam swap. Yeah, thanks for that.
Resetting ECU and retesting now. Will check the carbon can too.
...
OK - so car is now about 50% better. Shunting still pretty bad but at least driveable however the car won't take full throttle as it feels like it's holding back. I'll try again tomorrow and report back.
Edited by dumbfunk on Monday 13th June 17:29
dumbfunk said:
Thanks all
@ Mpoxon - I already had this problem when a previous specialist (Not Dulford) chose to badly glue up a crack in my distributor cap rather than spend the tenner to replace it after a £2k+ major service and cam swap. Yeah, thanks for that.
Resetting ECU and retesting now. Will check the carbon can too.
...
OK - so car is now about 50% better. Shunting still pretty bad but at least driveable however the car won't take full throttle as it feels like it's holding back. I'll try again tomorrow and report back.
That really is shocking that someone would try and glue a crack in a dizzy cap rather than replace it under any circumstance let alone during 2ks worth of work. @ Mpoxon - I already had this problem when a previous specialist (Not Dulford) chose to badly glue up a crack in my distributor cap rather than spend the tenner to replace it after a £2k+ major service and cam swap. Yeah, thanks for that.
Resetting ECU and retesting now. Will check the carbon can too.
...
OK - so car is now about 50% better. Shunting still pretty bad but at least driveable however the car won't take full throttle as it feels like it's holding back. I'll try again tomorrow and report back.
Is the dizzy cap that you have now definitely a genuine Lucus part as I know several owners who have been sold new caps as genuine Lucas parts and even supplied in the green Lucus boxes but they turned out to be cheap copies which caused similar issues to what you are having. The genuine Lucas caps I believe have a stamp on them.
Apologies if you have already checked that previously, it is just sometimes the simple things are overlooked.
Best of luck with the issue
Firstly thanks again - I think we've cracked it!
I gave it another day for the MAF to dry out then today pulled all the plugs and cleaned the soot off them. As a result the car is 98% fixed - the missing 2% is down to a slight hesitation between 5-6k rpm that I'm hoping will disappear when I put the new, non-soaked air filter on the car tomorrow (unless the plugs have finally had it).
What is amazing is that nobody I've ever asked about this exact problem had suggested this in the past - perhaps there are so many other possible water related electrical issues that the diagnosis gets clouded and by the time the car is at the menders it has all dried out? Either way whilst it's disappointing to think how much time and money I spent on new leads, extenders, dizzy cap, fuel regulator and coils over the years trying to trace it, I'm delighted it's solved now. Next step is to make sure the problem doesn't reoccur with the Pipercross filter.
I'll ask the Mods to add a "Solved" to the thread title to help others find it in future.
Cheers!
PS: Derek - I certainly did check your excellent resource. It's been useful a number of times over the years so thanks for putting that together! Feel free to use this story if you feel it is useful.
I gave it another day for the MAF to dry out then today pulled all the plugs and cleaned the soot off them. As a result the car is 98% fixed - the missing 2% is down to a slight hesitation between 5-6k rpm that I'm hoping will disappear when I put the new, non-soaked air filter on the car tomorrow (unless the plugs have finally had it).
What is amazing is that nobody I've ever asked about this exact problem had suggested this in the past - perhaps there are so many other possible water related electrical issues that the diagnosis gets clouded and by the time the car is at the menders it has all dried out? Either way whilst it's disappointing to think how much time and money I spent on new leads, extenders, dizzy cap, fuel regulator and coils over the years trying to trace it, I'm delighted it's solved now. Next step is to make sure the problem doesn't reoccur with the Pipercross filter.
I'll ask the Mods to add a "Solved" to the thread title to help others find it in future.
Cheers!
PS: Derek - I certainly did check your excellent resource. It's been useful a number of times over the years so thanks for putting that together! Feel free to use this story if you feel it is useful.
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