Ignition Cutting Off

[stewartdjones]

Hi all, the saga continues; I have take all the comments from you Marlinersbut have now narrowed it down to an electrical issue.
Here is the list of what I have replaced:- electrical ignition module, distributor cap, coil, throttle position sensor, idle speed solenoid, crank position sensor, both engine management relays (XI 70 / D 69), ignition switch, battery and both fuel pumps.
Question: could it be the main EEC IV module?
Any idea folks

[andyf]

It could be a wiring issue rather than one of the devices in the system. I had this with a simple fuel pump the connection was made via a relay and the connection from the switched live to the relay was intermittent, took me ages to figure out. A length of wire with a crock clip at each end is your friend as you can short across any potential breaks for testing.

[stewartdjones]

Thanks Andy for that, I’m about to fit a new alarm system in so will check all connections and wiring associated with the engine systems.
Just an after thought, the intermittent fault only starts after I have driven approx 10 to 12 miles.
Again any other thoughts guys?

[andyf]

That's consistent with the issue I had. It would fail after a while and then restart if I stopped and let it cool down. It was very confusing, and the cool down period had nothing to do with it re-starting!

[dave_kitson]

This sounds rather like the problem on my 'other' car (Volvo 480). Starts and runs ok, but sluggish, and once warmed up misfires badly. Even cuts out on occasion, but fortunately restarts. I tried all sorts of fixes to the electrics - temp sensors, coil, etc, but no change. I had the injectors cleaned and the ECU tested. Still no joy. The car is now in a garage to try and find what gives.

Initial test was to disconnect the air filter and blow smoke into the trunking, which resulted in smoke coming out by the air temp sensor and round the throttle control body. On closer examination, the latter appeared to have been sealed with silicone at some point! It needs cleaning out and sealing properly, to see if things improve or whether there are other issues. However, if there are air leaks, then under load the engine will pull in extra air. This will likely upset the ECU and cause running problems. It is still under investigation, but it may be something to check on your car.

Cheers - Dave

[stewartdjones]

I BELIEVE IT IS CURED
Thanks andyf
I replaced the fuel pump micro relay and so far no problems, have taken the car for long runs over very bumpy roads and the car works perfectly - fingers crossed.
Plan to do a 120 mile trip in a couple of weeks
again many thanks Andy
Regards
Stewart

[andyf]

Good to know you got it sorted.