ekeeton

I've lurked for quite a while but this is my first time starting a thread.

The car has been running great for about 4 months after I got it. When I bought it I took it my mechanic to put it into good shape and eliminate any PO "surprises". I drive a lot for work so I put in around 20K miles in this short time. The car has cosmetic issues but man does it run!

Anyway, I let my wife drive it for a short 5 mile errand one day about 6 weeks ago. She calls on the way home to tell me the console is saying "Engine temperature too high". While she's talking she then reports that the light has gone out (she had been sitting at a stop light.) The next moment the console tells her "Check range", then the engine temp warning came back on. Anyway, she was less than a mile from home so I told her to just drive it home.

After she gets it home, I figure out after a while that the fans aren't coming on. (Also the gas was low.) So, while in the process of troubleshooting the no fan issue, the car suddenly won't start any more. (After maybe 6 starts sitting in the driveway. I didn't keep it running long because of the temperature warning message.)

Trying to get it to start, I run the battery down, and so, try to jump start it. Cranks fine, but won't start. Put about 8 gallons of gas in the tank. It has a new fuel filter. Recharge the battery, slowly, and next day try to restart, still no dice.

Switched out the usual suspect relays with a known working one (the horn relay). No happiness. And the suspect relays do work for the horn. Check all the fuses, (only bad one is the aux fan fuse, forgot the number right now.) Go through the whole checklist litany with my mechanic over the phone. Still no start.

Bridge the fuel pump relay for a second and the fuel pump kicks right in. Now I'm starting to hear ghosts so I figure the LH unit maybe got fried when I tried to jump start it. (I didn't realize that was dangerous to the brains.) So I send the LH out to Louis Ott who graciously tests it before sending me a replacement unit, and it tests out fine in his S4.

So now I'm trying to think just wtf I have to do to convince this car to start again.

I'm concerned about trying to start the car with the fuel pump relay bridged because of the fire possibility. Is this being overly cautious?

I thought it could be the alarm system, but I think I eliminated that. I set the alarm by locking the door with the key, saw the LED lights blinking on the door locks, then unlocked and opened the door. Repeated this several times. Does this prove anything? Is there a better way to be sure the alarm system is working correctly without taking apart the glove box?

The next thing I'm going to do is dig out my timing light to check for spark. (I used to just pull out a plug and hold it near the block to look for a spark, but that was years ago and I'm not certain this is the right technique for this car.)

After studying the archives here, I'm guessing that my problem is the crank sensor. (I'm guessing that I won't have spark.) Is this a difficult thing to replace?

Are there any other ideas? Any one with the 928 wrenching sickness living close to Florence, SC can earn free beer and maybe even dinner if they want to have a garage party with me.

Thanks to everyone here. This forum is the only reason I felt confident to buy my 928 in the first place.

Chester89

I had a very similar experience. However, I didn't receive a warning on the console. Timing belt snapped.

Jim bailey - 928 International

If the water pump siezed that would explain the overheating so quickly....also could explain why the car will not start ..... timing belt may have failed jumped time. When the pump stops turning the pulley gets very very hot and then when you stop the belt melts and vulcanizes to the pulley....crank it and the belt may break. Pull of the dist cap rotor and cover on the passenger bank and inspect the belt...I hope I am wrong

docmirror

This is a back to basics thing. Your write up mentions that you can crank if fine, and it's doesn't crank hard. One of the big failure items in thrust bearing failure. Hoping you don't have that, it doesn't sound like it.

You need three things to run an engine. Compression, a properly timed spark, and a correct fuel air ratio. Compression can be affected by the timing belt, so take off the pax side intake duct and using a flashlight look in the little hole in the cover just behind the dist for the timing belt. It should not be frayed, ripped, etc, and should be tracking right.

If you have a compression tester, you can take out the front plug on each side and test for compression. While the plugs are out, put them back in the ignition leads and we'll check for spark. Set the plug ground on the cam cover and crank the engine. You should see blue spark from each bank. The compression should be between 130-160-ish. Look at the plugs for fuel residue. The color should be light brown.

Put the plugs back in and the ignition leads. Get one of those clear spritz bottles that glass cleaner or something comes in. Crack loose the front fitting of the fuel rail. Just loosen it a turn or so. Put the bottle over the fuel rail plug to catch the fuel that will come out, and crank the engine. Tighten the fitting, and get rid of the gas.

Let us know how these steps go.

<Edit, follow Jim's advice first might be best. You can also check gross cam timing with the dist cover off as well. >

Mrmerlin

the CPS is under the aircleaner on top of the engine its held in with a 5 mm cap screw.
If the connector is crumbling then you should also consider to replace the intake wear items knock sensors ,fuel lines ,TPS , idle control valve hall sensor and the flappy pot and all of the rubber hoses under the intake.

To remove the CPS you should spray the area with PB blaster first the sensors seem to become one with the block and usually you have to destry the old one to get it out, If its stuck try drilling a hols with a small bit and then screwing a long screw into it and then pull it straight up

ekeeton

The water pump was replaced when I had the major service done in January. Also new cam gears, timing belts and tension rollers, hall sensor and two new knock sensors, among other things. It's nevertheless entirely possible that they could have failed prematurely so I'll go out and check the timing belt.