SteveNick

This is long but it bears explaining.

After 5 months in storage I went to get the car out (89 951) . It started up no problem. Let it run for a few minutes then shut it off to move something out of the way. When I got back in the car the LED for the Central lock system was lit. I'm sure I didn't hit the toggle switch. As soon as I cranked the engine the alarm went off. Couldn't shut it off even with the key in the door locks. I disconnected the battery , made sure all doors were closed, hatch closed, radio engaged, door locks not locked, then re-connected the battery. Again, the alarm goes off and can't be disabled short of pulling the battery negative lead.

I suspected a microswitch alignment problem due to replacing the door handle last year, so I pulled the fuse for the central door locks and voila! the car starts and no alarm! I then spent a few minutes jockeying the car back and forth to wiggle out of the storage spot and stalled the car. It wouldn't re-start (but at least no alarm).

Eventually, after 2 hours of random attempts, the car starts up and runs like a top. I didn't think to use my spare (re-furbished) DME Relay as I installed a new one last year when I had an intermittent starting problem which seemed to have been solved by the new DME Relay (which looks good, no corrosion or solder cracks). The car has new wires, distributor cap, rotor, plugs and fuel filter and runs great once it starts.

Next day, the car won't start, cranks over fine, but no go. I replaced the new DME Relay with the spare and the car starts. That evening, same routine, swapped the Relays and the car starts.

Yesterday same deal, the car won't start. Only now, swapping relays has no effect. At this point I'm thinking it's not a relay problem so I pulled a plug wire, installed a spare plug and checked for spark. There is spark and the car decides to start.

Thinking I can at least now take the car for a spin I shut it down and replace the plug, only once again it won't start!

I've pulled the cover off the DME/Alarm unit in the passenger footwell and everything looks like new in there, no corrosion anywhere or signs of moisture.

I'm no electrical whiz but I suspect this has something to do with the initial alarm problem. I need to get this fixed because after 5 months I need to drive it but I can't enjoy it knowing it's probably not going to start if I shut it off.

Any thoughts?

SidViscous

Check the wires that interupt the coil power wires from the alarm. Could be an intermitent problme that is killing the power to the coil.

Or even putting some resitance on the 12V low power to the coil can also cause problems.

SteveNick

Sid;

I'll check your suggestion out.

Is it possible to do something as simple as pulling the fuse for the alarm system to disable it, or will this disable the ignition system as well?

Given a choice I'd rather disable the alarm completely. I don't really need it. The car's not a daily driver, car theft is virtually unheard of around here and when I do drive it it its rarely out of my sight. It's just a pain in the butt at this point.

SidViscous

YEs and no. If the alarm is acting flaky and cutting out it could solve it. If the connection in the wiring loom is bad it wont.

Follow your two wires from the coil back and see what you can find.

Best way is to power the coil direct from a 12V source that is on with the ignition, but I think in our cars the DME has to have control. But any interuption in the middle is not a good thing.

silicondigital

There is some "green wire" to cut going from the alarm to kill it i think. Someone will know. First off id replace the realy with a NEW one.