1978 Chevrolet C1500 - Page 7 - Answered Questions & Fixed issues

Then the wiring to the pump is shorted inline or the connector to the pump has burned terminal which causes an over current issue and can blow the fuse. You did change the fuel pump connector correct?

check your heater core Chevy is bad for that if water pump goes out heater core will to hoses go from motor threw fire wall leak will be coming out of fire wall between hoses

04/11/09 2000
Chevy Cavalier Air Conditioning Clutch replacement
Just finished it. I am an novice. Use safety glasses, Dust and dirt will get in you eyes even with the protection.

Disassembly:
Pop and raise the hood.
Loosen the left front lug nuts. Jack up car the higher the better. Install jack stands! Remove left front wheel. Place wheel under car to act as a last chance stand in case your jack stands fail.
Using 9/32 nut driver remove screws that hold plastic shielding to the inner fender well so as to expose AC compressor.
You will also have to pullout the Plastic snap things with needle nose pliers so get the plastic covers away from you work area ( I didn’t remove ALL of the plastic completely, just enough to swing it out of the way. There is a box of electrical stuff right there (wires) but the screws that were holding it to the inside wheel well had rusted away so it moved with the plastic when pulled out and away.
Pull down on the belt tensioner to loosen the serpentine belt (its hard to do) and slip the belt off of the AC compressor pulley.
Disconnect the AC Electromagnetic clutch power wires, (it is facing the front of the vehicle) the connector has little "Wings" that must be "Slightly pried apart" in order to remove the plastic connector from the compressor.
Using a 1/2" socket remove the nut that is in the center of the clutch assembly (to remove- turn it counter clockwise), I used a pry bar against the upper control arm and a notch in the Outer clutch plate to hold the A/C outer clutch plate from turning as I turned and removed the nut.

IMPORTANT! This nut that you are removing is threaded on to the A/C compressor shaft. DO NOT DAMAGE the A/C compressor shaft or the threads on which the nut is threaded.

NOTE: Be aware there is a "KEY", a small rectangular piece of metal that is on the shaft of the compressor, it will either stick to the outer clutch components or to the A/C shaft. This key is what transfers the belt energy onto the Compressor shaft (do not misplace).

This outer clutch plate is to pull straight out to leave exposed the inner clutch plate.
I suppose a few screwdrivers or chisels may do the trick but this part must come off of the compressor to get to the important next part.
I used a TIE ROD End Puller to slide the outer clutch plate out and off of the compressor shaft.
By driving the tie rod tool between the outer and inner clutch surfaces the outer clutch slid from the compressor shaft. Any wedge type device should be able to do this.

IMPORTANT! There is a "Hidden" C clip (snap ring) behind the outer clutch plate! ( I did not know this until I broke the end of the compressor nose off by pulling the pulley off with a pulley puller). Please read on...

The "C" Clip. This clip uses snap ring pliers to be removed. This clip holds the inner clutch assembly onto the compressor. The snap ring is holding onto the "Nose" of the compressor.
This clip is now "closed" you must "open" the clip so that it can be pulled off of the nose of the A/C compressor.
I used "Snap Ring Pliers" but I suppose a "Ground-to-a-point" Needle Nose Pliers "May" work.
Once you have removed the retaining ring the next thing that comes off is the inner assembly.
I used a pulley puller to remove the pulley but the Auto parts store in which I purchased the new A/C clutch would let me "Borrow" the AC clutch puller tool. This is the way to go if you are doing this on a budget. The A/C clutch puller grasps the A/C pulley on two sides and pushes against the compressor shaft, thereby sliding the inner clutch assembly EVENLY out and away from the A/C compressor "Nose".

IMPORTANT! DO NOT DAMAGE the A/C compressor shaft you will not be able to repair it if you do!
With the inner clutch assembly removed, the last thing to come off is the fragile A/C electromagnet, If you need to replace it.

The "Electromagnet":
This is a plastic coated coil of fine wire that electrical current flows through when the A/C is turned "ON" inside the car. When the current flows through it, it creates a strong magnetic field and this magnetic field pulls the outer A/C clutch parts into contact with the inner A/C clutch parts until they touch. This force is strong enough to transfer the spinning energy of the serpentine belt through the clutch onto the compressor shaft (by way of the "Key") and turn the insides of the A/C compressor to compress the liquid coolant and send it on its way through the A/C hoses.

This electromagnet came with the new clutch assembly I purchased so I changed mine. (I broke the connector off with a screwdriver earlier so I'm glad I got a new one).

NOTE: Notice where the magnet electrical connection is facing (forward- you'll need to remember).
I used several screwdrivers to evenly force the "Magnet" off of the Compressor "Nose".
It must move about 2" before it falls off, so I ended up using some "wedge like" chisels and screwdrivers to force it off by driving them between the A/C case and the back of the electromagnet (it took about 3 minutes).

Congratulations IT IS APART! Now to put the new parts back on.

New parts: Electromagnet, Inner clutch, Outer clutch
Parts to re-install: the "Snap Ring" ("C" clip), the "KEY" taken from the old outer clutch assembly (or "off of the compressor shaft" wherever it ended up being).

Position and install the new electromagnet onto the A/C compressor "Nose". Be aware of the position of the electrical connector is to face "forward" (like the way the old one was positioned).
I used the old electromagnet to be a sacrificial part when I used a small hammer to drive the new part back onto the "nose" of the Compressor. I drove it until it was almost touching the compressor bolts. (The same position as the old one was before I drove it "Evenly OFF of the Nose" with my wedges and screwdrivers).
Position and install the inner clutch assembly onto the compressor. Apply pressure evenly so the part does not "****" sideways and become stuck. I gently tapped around and around until it bottomed out.
NOW install the Snap ring using the tool you got it off with (It should just about "Push on") until it "Snaps" (locks) back into the slot that you removed it from.
I applied an anti-seize agent on the inside and outside of the shaft of the new outer clutch before I lined it up with the compressor shaft. Remember to install the Shaft "KEY" between the shaft and the notch of the outer clutch component.
Press the new outer clutch back onto the compressor. (I used a small hammer and "Gently" tapped it to where it should be.
Install the 1/2" nut you removed from the center shaft and turn it Clockwise (Tighten) until it bottoms out.
If necessary tap the outer clutch assembly until you are sure it is back to where it should be. There should be a small gap (postcard thickness or so) between the inner clutch and outer clutch surfaces.
Using your 1/2" socket be sure the nut is TIGHT ( I have no idea what the torque specification is or how to hold the outer clutch assembly from turning so I held it with my hands until I couldn’t stop it from turning).
Plug in the electrical connection.
Re-install the plastic panels using the 9/32" nut driver on the mounting screws. Snap back in the plastic fasteners into the holes from once they came.
Re install the left front tire into the car and tighten the lug nuts to the specified torque.
Carefully remove the jack stands and lower the vehicle to the ground.
Inspect your work clean and put your tools away.
Start the car, with the AC Button (Switch) "OFF" inspect the outer A/C Compressor Clutch "not turning". Listen for problematic sounds.
Turn on the A/C, with the AC Button (Switch) "ON" inspect outer A/C Compressor Clutch is "engaged" and turning the shaft of the compressor. After a few minutes the cabin air should start to cool.
This is how it should work.
With mine, the clutch did not engage, Probably because there is no refrigerant in the system so the compressor will not engage until I install at least one can of refrigerant into the A/C System (that's when a pressure sensing switch figures out that there is refrigerant in the system and it will be "OK" to run the compressor). You cant run the compressor without it's lubrication it wont let you.
So now I'm off to the parts store for a couple of cans of Freon (or what ever its called now).
I hope this helps - Good Luck!

Do you have a 1, 2 or 4 wire plug?

Drivers side under dash by the fuse panel

What year and engine size?

Had it acted up before this ? Any recent work done on it ? Will the engine turn over at all ?

I have a 90 chevy k1500 350 tbi with same problem! I have traced problem to... after turning on key fuel pump kicks on when u crank it over injectors shoot gas and truck starts! After few seconds injectors stop spraying and truck dies! This can happen many times over and over! Eventually sometimes truck stays running and all is great! I changed ignition module, oil pressure sending unit (which i was told controls gas after vehicle is running) fuel filter, computer, fuel pump relay, I am at a loss now! Hope this helps and hope someone can help me!

When it starts does the oil pressure gauge rise. TBI's use a signal from the oil pressure sender to keep the fuel pump running.

Going on the information you have provided it sounds to me like the fuel pressure regulator.It is located unthe intake manifold and is a lenghty job to do and is exspensive to have done.If you have a good mechanical ability it can be done by yourself in about 4-5 hours.and cost about $100 bucks.

this is an evap emissions code dealing with a bad evap canister purge valve or purge valve solenoid. To test for these most mechanics will use a smoke test to find where the leak (if any) is located.

The auttomatic idle module is nor workong

Clean the mass air flow meter.

That is the filter bypass valve. If the oil filter plugs up then oil pressure opens the valve to let unfiltered oil back into the engine so it won't destroy the engine.

A shorted diode in the alternator will draw down the battery.

Chilton Manual will have the diagram you need.. You can get them at most auto parts stores.

get a test light and see if you have power at the bulb plug, yes there is a fuse for lights ....find it and check it... I had 3 chevy/gmc trucks and they all had two fuse boxes one under dash one over drivers front fender well... check for power at fuse/relay (pull the fuse out connect your test light to a ground - one side of the fuse socket should have power (with light switch on) if it doent it is probably the switch at the dash... 0

The 2007 and up Avalanche, Escalade, Trailblazer, and other GM trucks changed the design of the bottom of the steering shaft. For no discernible reason, it has a horseshoe cup at the bottom of the shaft that prevents just sliding the old sensor off and putting the new one on like in 2006 and previous models. Therefore the entire steering column has to come out of the truck which is, to say, highly annoying. Disconnect battery and ground negative lead cable to the frame or leave disconnected for 10 minute to discharge ABS system. Pull steering wheel ABS cover - 2 small alan wrench holes on either side of the airbag, spring-loaded, pull gently while turning the wrench. Disconnect both airbag clips (don't lose the retaining clips!) and remove airbag. Remove lower plastic knee trim (where your knee or shin would touch at the bottom of the kick panel). Disconnect all steering shaft electrical connectors - there's quite a few. Under steering column, unbolt upper driveshaft 15mm nut. Remove 4 16mm steering wheel nuts. Pull steering wheel out of car, lay on bench. Remove steering wheel shaft upper protective sleeve (the part that has the horseshoe end shape that prevents the SWPS from sliding off when you're trying to remove it that serves no useful purpose except to turn a 15 minute job into an hour and a half of irritation). Gently unclip 3 retaining clips of SWPS rear cover (4 o'clock, 7 o'clock, and 12 o'clock on the shaft), slide off, then get a screwdriver in behind the old sensor and gently move it backwards a little so you can get your fingers on it, then slide it off. Put new sensor on exactly the way the old one was on. Note, DO NOT remove pin until this assembly is back in the car and connected to the electrical harness. Slide SWPS cover back onto shaft but do not clip into place. Put steering wheel back in car, connect all bolts and wire harnesses. Remove pin. Re-install plastic cover. Start car, drive to dealership, hook up to Tech 2 and have them run the full SWPS re-learn procedure, which they will probably charge you an hour of labor for anyway, then take your half hour of saved labor money and go buy yourself lunch. Alternately, save several hours of cursing, make a turkey sandwhich at home to save eating out lunch costs, and let dealer do the whole thing.

Okay it says you checked starter motor and it tested good. what test did you perform? A bench test would tell you if solenoid is good or bad. Try this With starter in vehicle and key on, jump positive power to solenoid it should spin and engage flywheel and start vehicle

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