this is it i cant take no more

[redmatt]

well im back with an update, sunday again! so i replaced the throttle potentiometer,the cold start injector,the pressure regulator and the vacuum advance unit, got even more petrol, went and checked cables were in place in the engine, bay couldnt find any out of place, car again idled lovely reved lovely popped as only a tvr can, ticked over at about 800, drove to the end of the road it was fine, pulled out it was fine, 1st gear ok 2nd seemed ok then got to 40mph ish very steadily 2500 revs and engine cuts out completely no power at all! foot of gas car picks up again if no full acceleration made car goes ok just will have to be the slowest tvr on the road. oh and no major a roads in my journey just have to drive in the residential streets at 30 mph, i dont expect any body to respond, as this is probably boring you to bits and you'd all rather be in the garden with a cold beer, but i thought i'd tell you about it anyway,

[stainless_steve]

Sorry to hear your still having problems
How about taking it to a Wedge friendly garage, is there one near you?
Edited to add you might as well light the BBQ and have some too

>> Edited by stainless_steve on Sunday 2nd May 16:35

[streaky]

What SS said, but don't give up ... it could (all too easily) fix itself! - Streaky

[redmatt]

You know what ive been thinking back to the start of this problem and it seemed to be when i put new spark plugs in and changed the ht leads, im know thinking how can i have caused this to happen doing such an easy job, could i have affected the engine so much. Please someone tell me that my machanics skills arent as bad as i'm now thinking. The clown is because thats how i know feel. Thing is the car was fine anyway just thought they havent been done for ages (according to the previus owners docs)and it might just be a good idea

[350matt]

OK a couple of questions:
Does the car rev up ok when out of gear / sat idling? (a bit of hestitation when cold is acceptable)If yes then the basic engine is probably OK and spark timing probably also OK.
If not then check that all the HT leads plugged in fully to the dizzy and on the plugs? As this can cause interference / noise with the dizzy pickup
Next check fuel pressure with a suitable gauge ( you can plumb it instead the cold start injector on the side of the plenum) should be 2.5ish Bar / 36Psi with the engine running, blip the throttle and the pressure should be maintained.
From your description it sounds like fuel problems so check your injector wiring loom and the 'power resistor pack' on the wing.
If you ask the factory they'll post you a wiring diagram which should be taken as advisory but is helpful none the less.

Best of luck, it'll be worth it
Matt

[bobfrance]

I'd certainly check out the fuel pump (if you haven't already).

In particular the connections to it. I guess yours is positioned in the wheelarch(a terrible place for it)as mine was in my 280i.

It gave me constant (intermittent) trouble until I changed it and renewed all the wiring and connectors leading to it.

Also I suppose you've changed the fuel filter and nobody has put sand or a plastic bag in your fuel tank?

[redmatt]

it revs fine when idling, sounds fantastic, ill check the things that youve said, in know your right it will be worth it just frustrating when the suns out and you want to go driving still i'm learning more stuff every day and so is me partner whether she wants to or not

[redmatt]

ive had to bypass the relays and fuses with the fuel pump wiring as the fuel pump wasnt working changed that a little while ago and just have a switch in stead to turn it on and off but it did work as normal with this in place

[bobfrance]

Watch out if you're using a switch without any relays.

Mine had a hidden fuel pump cut-off switch fitted by a previous owner as a security measure.

It slowly melted (probably over years)and one day left me stranded (until I figured out what was wrong).
I just consider myself lucky it didn't start a fire.

Another favourite is those little blue snap-on connectors as used by cowboy auto electricians.
My 400SE used to sometimes cut out when I went over bumps. Or rather it did until I removed every last one of the damn things and re did the job properly.

Don't give up hope matey!

[seamus]

Stick with it Matt.. sounds like you're getting there now.. nearly always something simple but has a large tendancy to annoy at the time.. been there several times as many wedge owners have and the good times definitely outweight the occasional niggle..

[rev-erend]

It sounds a little like the ECU is switching to get me home mode ... swap the ecu with someone local to eliminate it ..!

Are you hotwire or flapper airflow..

(I'm hotwire).

[dickymint]

Did you ever sort out the alternator problem?
Tried putting the old leads back on?

>> Edited by dickymint on Monday 3rd May 12:09

[redmatt]

now dont laugh this will just make you wonder about lady luck! when i got this 350i within only a few weeks i had some problems with fueling and ultimately misfiring, took advice on the phone from tvr specialist was told it was the ecu trying to overfuel, luckily i had a second 350i that is in bits so i swapped to see if it made a diff and it did, ran fine. Problem i have now is that im not sure that was the problem in the first place, as this is simular to before. I cant swap them back (oh mines a flapper unit)as i wont know one way or another. When i had the problems i changed the fuel pump just in case, thats when i put a switch in to turn it on and off (tempory fix )

[redmatt]

yes richard i used the alternator from the other tvr (thats in bits), changed the whole lot over at that time didnt help but replacing the battery sorted the electrical stuff that i've mentioned before.

[dickymint]

Ok. Check to see if the plugs are wet when it stops.
you mention that it may have been overfueling.

I had similar (two seperate occasions) As Wedgie1 mentioned before suspect temp sensor.
Secondly check the wiring loom that goes in line with the bulkhead for breaks where it rubs.

[redmatt]

dickymint said:

Ok. Check to see if the plugs are wet when it stops. you mention that it may have been overfueling. I had similar (two seperate occasions) As Wedgie1 mentioned before suspect temp sensor. Secondly check the wiring loom that goes in line with the bulkhead for breaks where it rubs.

[redmatt]

richard that temp sensor is it the one next to the thermo time switch

[350matt]

Yes, the thermotime switch is the bigger one with the larger hexagonal base, the ECU one is just to the right of this. Have you tried looking at a plug when this happens? If its soaking wet then your're overfuelling, it does sound like fuel starvation tho'

Keep at it

Matt

[wedg1e]

350matt said:

If its soaking wet then your're overfuelling, it does sound like fuel starvation tho' Keep at it Matt

Not necessarily: if it's an intermittent ignition problem it might keep firing the fuel but not the sparks, which would give the same symptoms.

[carlos_the_wedge]

When you were changing leads etc. Did you look at the coil?
I had a severe misfire on my 350i many years ago, and I seem to remember I had to change the coil.

Should be easy to check.

I see you are in Essex, so I am happy to drive over and swap for a quick test.