924 loss of power/judder

[kilgore]

Hey, my 79' 924 has a (another ) little problem.

If I try to accelerate other then really gently the car shudders and lurches as if it's starved of fuel, change up and keep the power low and it runs fine.

It doesn't always happen and can happen in any gear.

We've checked the fuel injectors (as two were leaking) plugs, it's got a new relay, dizzy cap, leads.
It was ticking over really fast so we've lowered the idle and it gets worse.

I've got a fuel filter on order but not sure if I'm barking up the wrong tree?

Any Ideas?

Cheers

[Rasta Monsta]

Your FI system (Bosch CIS) hates vacuum leaks. Carefully go through the entire intake, checking hoses and rubber boots for signs of cracking. Consider replacing leak-prone fabric wrapped hoses with silicone.

Also check your ignition timing, following the procedure in FSM or Haynes.

If this fails, there are simple fuel system tests that need to be done, but which require a special pressure tester designed for C.I.S. J.C. Whitney carries one for around $60.

Good luck!

[ideola]

Be careful with the JC Whitney site...they incorrectly list the EFI version as a CIS tester. They do have the correct kit, but it's really hard to find and their search feature typically comes up with the wrong one. At last check, they had increased their price to $65.

This is the one you want:

[Rasta Monsta]

FWIW, our host also sells one from Tool Aid (the one that I have), although it does cost a bit more than the Hoffman unit sold by JCW.