88 626 dies suddenly when warm

[hamilton101]

Hi - this is my first post - hope someone can get me going in the right direction on this.

My 1988 626 has about about 220,000 miles, and hasn't given me any trouble for ages.

Now, it's a headache. It starts easily and idles normally. Then, suddenly, it will die. Instantly. Then after that, it will start, run a few seconds and die. Any clues what is going on, here? Something to do with the Idle control in the throttle body?

If I get out on the highway it will run for miles, but if I slow down, it will quit in an instant.

Thanks.
Allen

MT, no turbo.

 

[xelderx]

If it did it all the time I would say it's a vacuum leak, but with it only being a warm motor condition it most likely points to a faulty sensor. I'm not 100% familiar with the electronics on you car, but I would start with the throttle position sensor. The factory service manual probably has a troubleshooting chart for warm idle problems, but you'll have to check with the dealer to see if they can dig one up.

 

[hamilton101]

88 626 dies

I talked with a neighbor, a retired mechanic, who suggested cleaning the throttle body. Couldn't get a socket on one of the nuts holding the TB so I cleaned on the car with the appropriate cleaner. Twisted the throttle to get access to the edges of the butterfly plates and the seats and scrubbed thoroughly with a toothbrush to get the dark deposits off. Guess the crud was sticking things together enough that air couldn't get through after the engine got past the rich start-up mode.

A few more notes - I removed the air intake and the MAF, first, and metered the resistance of the Idle Air Controller valve. Resistance was in range, per the shop manual. Didn't do any other tests. In the process of removing the above-mentioned parts, a plastic connector that hooks the stand pipe to the side of the air-intake tube just ahead of the TB. Ordered the part from the dealer and taped the hoses together with electrical tape. Oil appears to be coming from the valve cover through that pipe, so I'm considering just plugging it to keep the TB cleaner. And maybe cut down some on the oil consumption? Ah, the joys of an older car. We keep it around because it handles so well in the snow when we have to go over the Cascade mountain passes to get to my parents place in Idaho.

Thanks for the input on this, and hope some of this will be helpful to someone else.

Allen in Corvallis

 

[wicked]

I don't know much about what kind of ignition that car hasor much about this car,but........
most cars of that era use a ignition module in the distributor,this like all ignition modules when they get old,and start going out can short out when warmed up.


..........or,you may have a failing pickup in the distributor


........or if it's carburated you can have a cut-off in the carb thats failing.

if you bring this to a tech,he can test,and tell you for sure,shouldn't take much.

 

[xelderx]

Good to hear you have made some progress with it. You can plug that hole on the intake where the hose from the valve cover is supposed to go and then but a small breather filter on the valve cover. You can get the small breather filters at most autoparts stores.