Top 20 1990 GMC Suburban Questions & Answers

Rotors and brake calipers.

The actuator will not be on the front differential or drive line, it will be on the transfer case, which is mounted behind the transmission. Follow the front drive shaft back from the front differential, and the component at the rear of the driveshaft is the transfer case. That is where four wheel drive is engaged/disengaged. I'm not familiar with your vehicle, but if you have a separate lever to engage 4wd, there will not be a fuse for the actuator - it is a manual system. If the 4wd is selected electrically, check that all wiring and connectors on the transfer case are in good condition.

There is more than likely a short in the system. The third brake or a wire along the line. Try installing a circuit breaker while you are diagnosing the problem, then start removing bulbs and disconnecting wire harnesses and trying the brakes after each item is removed from the loop. Do one at a time until the circuit stops popping.

Will it start and or run with a shot of carb spray down the throttle body? can you hear the fuel pump running? have you checked to see if there is fuel pressure? I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

This question is asked so often it should be common answer by now. Check fuse, then ballast resistor (located under hood on heater box), then run hot wire directly to motor for quick test if motor is bad. If everything checks out good, bad heater switch is only thing left.

If you look at your starter wires there should be fusiable links there

check the cable coming from the back of the alternater going to the battery make sure it has current flowing throw it if not replace it

It could be many problems. Add some 'chem tool' to the gas tank and drive it for a week or so. Look into getting a tune up.

try checking your in line fuel filter, if you run low on gas, the pump will suck sediment off the bottom of the tank, and clog stuff up.

Well, according to my diagrams for 88-94 models, the alternator only uses the red and brown. There are pink-black wires that power some of the sensors and solenoids but should go to a fuse marked ECM in the fuse box. Have you tried hooking up the harness without using the pink-black wire ?

send issue to magicmechanic in orlando--hes a specialist and will reply

The common fault is that the fuel level sending unit is defective inside the gas tank.

best have vechicle pressure bleed since you have anti lock brake system.if you see brake light flashing you have brake failure either mastercylinder is faulty or still have air in brake system.let a garage fix brake system need tech 1 scanner to reset anti lock brake control module.

sounds like you have a bad freeze plug..unfortunately, you will have to remove the trans, torque converter, and possibly the flywheel to get to the 2 freeze plugs that are on the back of the engine

is it a 4l80e electronic shift transmission....it may be an issue with the solenoid pack...you can take it to someone who has a scanner tool for the trans...if it is indeed a 4l80e

The 1990 Chevrolet Suburban has the most common hook-end wiper arms. Locate and press the tab or button where the wiper blade is inserted into the hook of the wiper arm and pull wiper blade out of hook. You may have to rotate and flex the blade to make enough clearance for the hook to pass through.1990 Chevrolet Suburban Wiper Blade Installation Videos (hook-end arms)1990 Chevrolet Suburban Wiper Blade Size Options w/Correct Lengths & Attachments

the fuse box itself is marked, under each fuse, its easier to just check them all, with a test light it will take like a minute to check them all.

change the fuel filter ,, if its clogged you'd get the same thing

To begin with you are OBD 1, dont relie for a code its limited, there is a short touching ground, well first lets do the operation and work are way in 700r4 is a 4l60 so 1990 makes it a 4 or 3 wire connection so lets start here, (because it will make a trouble shooting tree sense) three terminal then trouble shoot it . on the transmission 1.Ignition(+) ,2. fourth clutch control 3. TCC control. . Here its three wire leading to transmission . The most problable is the ignition wire, that goes to the transmission when this goes it peg the speedometer, and because its ignition or IGN(+) we will be concern about this on,because without it it wont let you move the gear so lets follow its route and see where it will touch. something is interrupting this circuit. from ignition switch it goes to brake switch so look at the brake switch open the harness wire if you have to.and look for wire touching, then it goes to transmission Okay I am stump here also so OD is shorting (IGN+) Do this better it a all in one shot get the harness at the transmission its a three wire four pin connector inspect that connector open the harness if you have to , look for zip ties that may have squeezed open the wire together,trouble shoot the IGN wire from steering to OD switch ,you may have to replace the IGNition wire from brake switch to key area to transmission

what type of carburator is it, if its what is to be on the vehicle the filter is at the carburator, left front is the fuel pump one of the lines goes to the carburator, and the fuel filter is there going to carburator, let some one else do it you can easily damage the threads as you take it out why? you ll need a special wrench and this line can strip as it is loosen up,