3.5 efi wont start after running rough

timings off I reckon, it took three mechanics to get mine right! worrying really

Thanks again for all the help. Whats worth replacing when i go to do timing and why would it have jumped? Engine had been rebuilt before I got it and what would have caused timing to jump as it was running sweet up until last sunday??

Its all good experience i suppose !

Cheers again for the help

dont know, on mine the orginal failure was down to the amp module on the dizzy, I dont know if the ealier ones like yours have them? anyway that went then one mechanic took it out and then three couldnt get it back in right- they are a pita to do as it rotates on the drive gear as you slide it in.

has yours got an amp or have we been down that route, sorry I havnt read the whole thing.

by amp do you mean vacum on the side of the dizzy?

no its a little electronic amplifier. little black box- im not sure if the flapper systems have them but the hotwire does.

no mine has a vacum from inlet chamber (for advance) and a ignition coil. Really simple set up just wish i could get it to work

could it be my ignition timing is just to retarded? or adjust afm for more fuel possibly?

i dont see why your timing would have changed all of a sudden- you sure no one has been fiddling?

Nope was driving when it started missing. Left it overnight wouldnt start next day. Been checking everything so i had tried adjusting timing while someone cranked it over, adjusted afm as thought it was flooding? had fuel pump out also to check it was not blocked at the filter. Where could i get a gauge to check fuel pressure?

not sure , ebays always a good start lol

I would check that timing is right if its trying to start but misses. also fuel pressure worth checking as you say.

Like we said a while back, I had a similar problem where I drove for 40 minutes on the motorway, turned it off, started it up 30 mins later and within 2 minutes it started to splutter and then die, and wouldnt restart!

Turns out my ignition timing had gone miles out. Check this though:

Couldn't get the ****er running after 4 hours of messing about, borrowed a dizzy cap and it reluctantly fired up and then ran sweet for 15 minutes, where it then started to die again and wouldnt restart.

Whole thing made no sense.

All I can say is check your cam timing as best you can via checking both valves close on each cylinder before it starts it's compression stroke.

Run the fuel pump and then crack off the union on the fuel feed pipe at the fuel rail - fuel should spray out, hence good pressure.

Crank the motor with the plugs out and check that you get a good puff of fuel out of each plug hole just before the same plug sparks. Make sure the spark is nice and bright on each cylinder too.

Then it's all down to timing. Check and check again that on no1 compression tdc the rotor points to no1 tower on the dizzy cap.

Whenever my motors timing goes out or it gets flooded it coughs coughs coughs but cannot quite catch up enough to start.

Will yours run on easy start???

massive backfire on easy start - like a bomb going off!!!

so what caused your timing to go way out then noisy?

fett said:

so what caused your timing to go way out then noisy?

Click to expand...

nobody knows!

so kept you all the same components and and just turned the dizzy back to retime it and all was well? v odd

could the clamp have come loose??

Fett, Noisy and classic kev I cant thank you guys enough. engine is now idling again but still back firing will just need slight timing adjust tomorrow to dizzy (when i can get some day light). I think timing jumped originally due to bracket not being tight enough at bottom of dizzy and then backfire would have damaged vacuum hose and me fiddling with afm and idle setting didnt help either. However got there in the end and its all good fun cant wait to get back out on the road in my 90 again

Cheers

good man , I couldnt think how it could have moved otherwise! I have marked mine incase that ever happens- might be worth you doing the same when you get it back int he right place!

Good to hear it's running pal, no problem

Fett, I don't really know mate. I didn't change a single component and oncenit was adjusted it was great again.

The reason i didnt alter the dizzy on the off road day is because I had literally days before just rebuilt the dizzy with new advance springs etc, and reset the timing.

Can only assume the dizzy was stuck advanced when I set the timing, and something sprung back when it was warm and i started it up again. This is why it retarded with no apparent cause!

Anyway, glad to hear your 90 is getting there

well both cars are running now so we can all be happy, and I'll keep this one in my head incase it ever happens to me