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1994 850 Turbo cruise control and overheating

Mike F,

Can you tell me if the 1994 850 Turbo's cruise control vacuum pump is also located under the battery? Cruise worked intermittently at certain speeds then stopped and I suspect a vacuum leak in this system. Second question, do the vacuum lines for CC run to the switch on the steering column?

Questions for next round relate to engine overheating at idle after warm-up. Gauge fluctuates up to just below red zone but comes down once driving again. Needle is accurate as AC heats up rapidly with needle movement. Car still overheats with AC off. Radiator wad changed last week with no effect. Fan works as advertised. Still need to check water pump though.

Sparky

Reply to
Sparky
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Your cruise pump is indeed under the battery. The vacuum line goes only to a vacuum switch on the brake pedal, (and clutch pedal, if equipped) then to the actuator on the accelerator pedal.

If you're overheating at idle, and you're sure the rad and fan are OK, then I wouldn't hesitate about looking a the water pump. If it's bad enough to cause that problem, then you're living on borrowed time, and if it fails completely, the timing belt stops timing and you have bent valves and a very expensive repair bill.

Reply to
Mike F

Mike F,

I have looked over the entire cruise control system and cannot "see" anything disconnected or damaged. Do you recall the line configuration on the pump under the battery? I have one line going to the under-dash connection and another fitting, black with small hole off the pump. Should this second fitting off the pump be capped? Possibly the cap fell off? If my current condition were correct, how would I test the pump for pressure/operation? I suspect the pump but am not sure how to troubleshoot from here.

Sparky

Reply to
Sparky

Mike F,

I have looked over the entire cruise control system and cannot "see" anything disconnected or damaged. Do you recall the line configuration on the pump under the battery? I have one line going to the under-dash connection and another fitting, black with small hole off the pump. Should this second fitting off the pump be capped? Possibly the cap fell off? If my current condition were correct, how would I test the pump for pressure/operation? I suspect the pump but am not sure how to troubleshoot from here.

Sparky

Reply to
Sparky

Mike F,

I have looked over the entire cruise control system and cannot "see" anything disconnected or damaged. Do you recall the line configuration on the pump under the battery? I have one line going to the under-dash connection and another fitting, black with small hole off the pump. Should this second fitting off the pump be capped? Possibly the cap fell off? If my current condition were correct, how would I test the pump for pressure/operation? I suspect the pump but am not sure how to troubleshoot from here.

Sparky

Reply to
Sparky

Mike F,

I have looked over the entire cruise control system and cannot "see" anything disconnected or damaged. Do you recall the line configuration on the pump under the battery? I have one line going to the under-dash connection and another fitting, black with small hole off the pump. Should this second fitting off the pump be capped? Possibly the cap fell off? If my current condition were correct, how would I test the pump for pressure/operation? I suspect the pump but am not sure how to troubleshoot from here.

Sparky

Reply to
Sparky

Mike F,

I have looked over the entire cruise control system and cannot "see" anything disconnected or damaged. Do you recall the line configuration on the pump under the battery? I have one line going to the under-dash connection and another fitting, black with small hole off the pump. Should this second fitting off the pump be capped? Possibly the cap fell off? If my current condition were correct, how would I test the pump for pressure/operation? I suspect the pump but am not sure how to troubleshoot from here.

Sparky

Reply to
Sparky

The other line off the pump is just a vent, no connection needed. I don't have a diagram handy, but the pump should pump vacuum throughout the system. If you apply a vacuum to where the hose connects the pump (even with the engine off), the actuator should start to open the throttle. Pushing the brake (or clutch) pedal should dump this vacuum and close the throttle. The only problem I've ever seen with 850 cruise control other than vacuum was an electrical brake switch (the same on that turns on the lights) that was out of adjustment. There is no adjustment, to fix it I ended up bending the bracket it's mounted in to bring it closer to the pedal.

Reply to
Mike F

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