20 Most Recent 1987 GMC VanDura Questions & Answers

Check for vacuum leaks and test the idle air conrtol valve. TESTING See Figure 2

1. Disengage the IAC electrical connector.
2. Using an ohmmeter, measure the resistance between IAC terminals A and B. Next measure the resistance between terminals C and D.
3. Verify that the resistance between both sets of IAC terminals is 20-80 ohms. If the resistance is not as specified, the IAC may be faulty.
4. Measure the resistance between IAC terminals B and C. Next measure the resistance between terminals A and D.
5. Verify that the resistance between both sets of IAC terminals is infinite. If the resistance is not infinite, the IAC may be faulty.
6. Also, with a small mirror, inspect IAC air inlet passage and pintle for debris. Clean as necessary, as this can cause IAC malfunction.

Do It Yourself Diagnosis and Repair

The throttle body injector are turned on by a cam position sensor this is located in the distributor,

Is there B+ voltage to the injector ? Is the engine computer controlling it ? Suggest you watch youtube videos on injector control . Inside the PCM - engine computer are transistors which control the injector.

If it's anything like my 1994 Vandura, you have a small panel of rocker switchers above the rearview mirror for turning your interior lights and other gadgets(tv, vcr, etc) off and on.

The leftmost switch on mine moves the electric bench seat up and down, *and* forward and back. The trick is that you have to hold it down to make it move.

With mine, even though there are four actions:
- slide seat forward
- slide seat backward
- fold seat down
- fold seat up
there is only one rocker switch.

So what you do is hold "up" on the switch and see what it does. If it slides the seat in either direction, up for your van is for both sliding forward *and* back. To do the opposite direction, just wait a second then press the same button the same way a second time.

If up makes it fold, it's the same principle. Hold the rocker switch depressed in the up position to make it fold up. Wait a moment and repeat to make it go down.

It wasn't intuitive for me either but once you know and play with it a bit it makes sense. Probably better than having four switches up there anyway :)

Good luck!

just look for repair service here on fixya, and type your zip code and you will find the closes auto repair, does that answer your question?

I suggest check valve body and solenoids, could be clogged ot stuck.

There is most likely a cable that has come off or broken behind the heater controls

remove the oil filter and check that there are not 2 rubber gaskets in place (one in the filter and the old one that was stuck to the engine and came out of the old filter.) refit using a smear of grease ?oil on the rubber gasket and do up till it touches then about a 1/4 more turn . Do not over tighten or it will leak

There could be all kinds of reasons your vehicle runs rich. It should be fuel injected not carborated. It could have a bad injector, bad air filter, o2 sensors etc. Have it scaned for the reason.

go on line internet look for electrical diagrams or buy a haynes or chilton repair manual at any auto parts stores they have electrical diagrams.