Griffith cutting out briefly when warm

[FlipFlopGriff]

See my post 24th July.
FFG

[DarkMatter]

kabaman said:

I'd like to monitor fuel pressure whilst I drive along - is that possible?

Yes. I bought a fuel pressure tester on eBay, similar to this . The hose was long enough to run from the take off point on the fuel rail to inside the car so I could get a passenger to monitor the fuel pressure as I drove.

[kabaman]

And I discovered this...



The actual vacuum part was leaking too - despite it being only about two years old. Luckily I had a spare, so now swapped over. Since problem was temp related I don't suppose this was the cause (and I pulled the vacuum unit further out just for the photo) but another issues found. I've also swapped the thermostat for the correct 82C version.

Can't find any obvious air leaks though.

I'll take the new set-up out for a spin with Rovergauge and see what happens.

Cheers, Neil

[kabaman]

It's been a while since I updated due to one thing and another.

So...

I've changed the otter switch which has significantly reduced my relay chatter - so that red herring is put to rest.

I've replaced the vacuum advance unit which has helped with a bit of an air leak, and I've re-set the timing having had the distributor out.

I've put some spacers between some of the leads that were a little close.

I've checked a couple of the plugs which look fine.

Replaced thermostat with an 82C thermostat.

I've tested the fuel regulator for a vacuum leak - fine.

Car is generally behaving better and sounding crisper. I don't seem to get a misfire at exactly the same point in the warm up cycle as before. However I am getting an ocassional misfire, it seems to come an go.

I haven't changed the fuel filter for years - so that's a job I should have done anyway. I'll do that and check connections on fuel pump and see if that improves things.

N

[kabaman]

Well...I've waited a while to make this update just to be sure I had fixed the problem.

I removed the old fuel filter. I tried blowing through it and could but with quite a bit of resistance. I tried the new filter and could blow through it easily. I replaced the old with the new (not a bad job) and hey presto the car sounded different even on start-up.

I've done about fifty miles in it now and it's like a different car. The intermittent problem has gone - but it runs better across the entire rev range.

So the moral to this has to be to do _all_ the routine maintenance at the right time. I'd been meaning to change the fuel filter for years.

Anyway, one annoying intermittent problem solved.

Edited by kabaman on Saturday 21st September 21:26

[Rob_the_Sparky]

Thanks for the update, good to know what it was

[si easter]

Got a new fuel filter ive had for a while and was thinking of changing it so out came the Bible , drain the tank , is that really necessary ?

[kabaman]

I didn't drain the tank. I took the precaution of wrapping some cloth over the feed pipe to the pump and gently clamping with mole grips. I don't know if this is necessary but I've experienced in the past - rushing to do stuff with petrol pouring out and I didn't fancy repeating the experience. If you do this - go gently on the pipe.

Neil