Missing at high revs

[siwes]

My P reg 500 HC griff has since I got it a year ago missed at high revs approaching 5000 rpm it can miss quite bad it depends how quickly the throttle is pressed , quicker on the throttle the worse the missing. It went back to Blackpool for a service and it was a lot better new plugs coil etc , but the problem is back again . any help in the right direction is of course appreciated
Simon

[craigalsop]

Check the state of the HT leads, clean the stepper motor, how long ago was the service? Plugs may need changing again?
You may want to get the car to Mark Adams & get one of his ECUs & expert diagnosis/tuning on his rolling road...
(There are many other reasons that the car could be doing this, but they tend to be more expensive)

[icamm]

Also check the timing etc. I would suggest you find a good local specialist and take it along to them.

Mine had a similar problem, although not as low down the rev range, but was sorted at the next service by setting the timing properly.

Good luck,
Ian
red 4.3 Griff - E945 TVR

[beano1197]

Had similar (most pronounced at 2,800-3,400), cured by new HT Leads, plugs and a good clean under the dizzy.

[whitechimp500]

Have recently had same problem with my Discovery V8i.
Dizzy Cap , Leads and new NGK plugs cured it.

[mel]

I have got exactly the same problem at the moment. It went to Motovation for a service and because of the problem, it was diagnosed as being a faulty ignition module and was fine for 100 miles then problem back again this time they took off the ignition module cleaned all the connectors tightened it back up and it was fine again for another few hundred miles then problem back except this time I was down in deepest dorset, so on the phone they suggested replacing the HT leads (I'd found a tear in the insulation of one) and the heat shield/extension cap things on the plugs. Leads were no problem from local Land Rover dealer caps were a problem as Vauxhall dealer had none nor did their other branches. So off to Westovers for the cap things and as it was chucking it down they were extremely accomodating in giving it workshop space and a technician immediately! however the problem was still there so deeper they went. After 8 hours ! (genuine as I stayed in the workshop with the technician all day and he worked solidly) and having re changed ignition module to a genuine Lucas part and not a pattern part, compression tested, new coil, leads, timing adjusted I had a different car and a reasonable £500 bill (only actually booked 4 1/2 hours)

All seemed good and dandy only this time after 4 days and half way up the A3 the problem came back again worse than ever !!!! So a quick detour into Motorvation to find both Paul and Michael were "day off" bugger! Car is booked in with them again for tomorrow to try and get to the bottom of this once and for all. I've a horrible feeling it's going to be an ECU issue and expensive, the bloody thing has already cost about £700 to get no where. I know it is and intermitant fault that is hard to find and I realise it's not helped by keep thinking it's sussed only for it to return a few days later but this thing is begining to wind me up and getting expensive......

Will keep you informed.

[Leadfoot]

Is the timing being adjusted each time it gets 'fixed'? Maybe your dizzies knackered if so.....

[joospeed]

No disrespect to any of the talented guys who've worked on your car - i know these kind of situations all too well in TVR land but if you're getting charged for not fixing the fault something's wrong, you should ask for a refund on any money you have spent or get the repair done FOC this time since the parts have been changed for no reason (hope your old parts were left in the car since technically you still own them and they could be refitted). you should only pay for what actually cures the fault IMO (dificult situation though as the fault seems to be cured I know). seems fair to me anyway, the fact the fault appears to be sorted is immaterial. I have a car coming back in because I thought I'd sorted a fault but clearly hadn't - my mistake .. it will be fixed FOC no matter what i have to do and how much I have to spend to cure it, I'll possibly lose out big time but my customer should be happy. or is it just me that works like this??? teehee

[Guillotine]

nope...Penninsula does too - i hope!
will find out later this month.
seriously though, they've been great over the last few years.

[joospeed]

quote:
nope...Penninsula does too - i hope!
will find out later this month.
seriously though, they've been great over the last few years.

I have a few dealings with peninsula from time to time and I always get good service from them, very helpful guys.

[mel]

I have to admit I am normally one tight bar steward if I feel I'm not getting value for money, but I have got to admit that the service I got from Westovers was good enough for me not to begrudge what I paid them even though the fault came back, they have replaced most of my ingnition system which If I'm honest was probably close to the end of it's life anyway. I learnt stacks from the 8hrs I spent in their workshop with them and they fitted the car in immediately because of my situation when they are normally booking 5-6 weeks in advance. They gave me a good honest service and believed truely that they had fixed the problem and I'm not about to travel back to Dorset to get them to look at again, even though I'm sure they would. As for Motorvation they have also been very good to me and I can't honestly blaim them for not fixing it in the first place as they did think they had. I spoke to them on Friday and as suspected it is an ECU fault that warrents a new one, well new to me atleast they are looking for the cheapest option and I'm also talking to a "friendly" local Land Rover dealer as the chips in mine seem ok and can be swapped over, I don't mind paying for the parts I have but I do take your point about paying for the labour. cheers Joolz shame your up north

[joospeed]

quote:
I have to admit I am normally one tight bar steward if I feel I'm not getting value for money, but I have got to admit that the service I got from Westovers was good enough for me not to begrudge what I paid them even though the fault came back, they have replaced most of my ingnition system which If I'm honest was probably close to the end of it's life anyway. I learnt stacks from the 8hrs I spent in their workshop with them and they fitted the car in immediately because of my situation when they are normally booking 5-6 weeks in advance. They gave me a good honest service and believed truely that they had fixed the problem and I'm not about to travel back to Dorset to get them to look at again, even though I'm sure they would. As for Motorvation they have also been very good to me and I can't honestly blaim them for not fixing it in the first place as they did think they had. I spoke to them on Friday and as suspected it is an ECU fault that warrents a new one, well new to me atleast they are looking for the cheapest option and I'm also talking to a "friendly" local Land Rover dealer as the chips in mine seem ok and can be swapped over, I don't mind paying for the parts I have but I do take your point about paying for the labour. cheers Joolz shame your up north

it's great that you can say you've had good service, that in itself speaks volumes for the helpful nature of these two garages. nice one

[craigalsop]

If you are going to have to shell out for a new ECU anyway, this is an ideal opportunity for a Mark Adams chip

[mel]

The chips on my ECU are "not standard" or "performance" as it is but their origin is not clear

[SCOTTYB]

Hi Lads


quote:- from Sivwes
My P reg 500 HC griff has since I got it a year ago missed at high revs approaching 5000 rpm it can miss quite bad it depends how quickly the throttle is pressed , quicker on the throttle the worse the missing.


Did the missfire get sorted ? I have the same problem with my 4.3BV ,changed plugs,dissy,rota fast running out of ideas !!

[mel]

Well my ones now sorted :fingerscrossed: I ended up with a new ECU which Motorvation were as good as gold with and didn't charge a penny for fitting, changing the chips over, or all the general buggering about on, so top marks to them for sorting out a really tricky problem as smoothly as possible.

Also another really handy tip on ECU's my new one came from a company in Derby in the end
www.all-car-electronics.com
These people are fantastic and offer an ECU "hire" service basically as ECU faults are so hard to track down and be 100% sure without thousands of pounds worth of kit and years of experience for £40 they will send you a replacement tested ECU to "try" if it cures the problem then you pay a pre agreed price for it if not you send it back and thats it. My ECU was a refurbished unit by lucas to the correct part number, the chips needed to be changed over from the griff but for £150 I thought it was a result and top marks again for Mike at Motorvation for finding them.

[siwes]

Thanks for all your replies ,
to date I have replaced the coil , new mag leads 8mm , new heat shields , new dizzy, new plugs,.
still the same , I will try thr timing next , I adjusted the air flow meter setting , slightly better but still the missing, one thing I did not mention was the car starts first time when cold but when hot its the very devil to get going , that was another problem Blackpool were meant to fix.
It is booked back there at the end of November for a new clutch and hopefully to sort these very annoying problems out.
I dont think its the ecu they are pretty reliable ,again thanks for all the replies Ihope to let you know what the problem is when its found.
regards Simon

[Guillotine]

did the amp come with the disty?
at £40-00 its worth ago.

[kevinday]

I refer you to this month's TVR Club magazine and the excellent article by Steve Heath which details a problem that sounds exactly like this.

[mel]

quote:
I dont think its the ecu they are pretty reliable

Yes but they do have a tendancy to "cook" if too close to the heater pipes.