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The car did nothing today after trying four different relays. I tried two (24) relays and two (53) relays for the fuel injection. Nothing changed. In fact, all of them made the car stop firing. Only when the injection relay is jumped will the car fire. As soon as I replace the jumper with a relay the car stops firing. Nothing changes when I spray starting fluid in the intake. It still sounds like it's so close to firing up, but no definite tick over. I'm sending my LH, and EZF to Rich, the guy who wrote that article on RL. That way I don't keep chasing a bad LH or EZF.
I've cleaned all of the grounds and contacts, so I'm going to let him test the computers and see what's happening. While the computer is away I'm going to do a compression test.
I'm not going to give up on this car. I bought the car for something to work on anyway. It gives me something to do. I really liked my U.S. 83 and 84 928's. I hope I get to find out what it's like to drive this car. I tell my wife that whether it runs or not it's still beautiful to look at. It's a work of art and the body on this car is really in great shape.
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Old 03-08-2017, 06:15 PM
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Rich Andrade will fix your computers if there is something wrong. IIRC, he fixed mine on the Schwartz car back in early 2000's.

As I told you in PM, 85 US computer can power your car, is plug and play, and allows you to swap chips if you desire. (JDS sells the chips for 84-86 Euro which I'm told are a real upgrade to the original factory chips) If you have to buy a new to you LH computer, find an 85.
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Old 03-09-2017, 07:15 AM
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Looking at the timing belt picts I would skip the "just get it running" stage and start fixing it. Very likely the heads will need to come off, certain it needs a timing belt service and new water pump, just cut to the chase.
Old 03-13-2017, 01:20 AM
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Compression -

Hey 924 - Once you had the cam and crank shaft timing marks corrected have you had the time for a compression check ? Just make sure to have the throttle plate held wide open during the test. I like to write down not only the 1st compression stroke reading but also the final (highest) reading on the gauge for a more complete cylinder performance comparison.

Many feel when troubleshooting a "No-Start 928", it is best to initially jumper the socket legs of the removed ignition and fuel injection power relays to help eliminate any potentially questionable relay.
Also - all the other owners were correct about spraying starter fluid through the LH "Hot Wire" air intake. I should have mentioned to only spray a light whiff into the plenum port used for the power brake connection.

Please keep us posted - Michael
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Last edited by JK McDonald; 03-14-2017 at 08:59 PM..
Old 03-14-2017, 08:41 PM
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Yes, I'm just trying to make sure the electronics are in working shape before I start to dismantle the motor. There is some indication from both previous owners that the car had some electrical issues. DanglerB, I mentioned that the pictures of the cams that I posted here above were with the crank set on the wrong mark. With it set correctly at the first OT mark the teeth were about 2 teeth off. So it was much less out time than in the pictures here, but still out of time by 1 or 2 teeth on each cam. Granted the timing belt is not in good shape, but it's mainly chewed around the edges from me leaving the left timing cover wedged open and the belt touching it as I cranked over the engine. The belt is not in terrible shape. It looks like a botched replacement. It has no cracks or teeth missing. I'm going to replace the timing belt and tensioner if I can fix the car with electronics. In the meantime, I've put the cams back in time with the crank, retensioned the belt, and spun the motor many times to check the timing. After continual hand cranks and starter crank checks the cams are now dead on. Let me see what the story on the LH and the EZF is. If they check out okay, I'll continue on to pulling the motor and report what I find in the internals. I'll post pics and you guys can cry with me. I appreciate the help you guys have given me so far. This is going to be a long process, but in the last couple of days I've sold a couple of my junk cars for scrap and I'm expecting the worst. Don't worry though. I have a passion for 928's so this project is going to get finished eventually one way or another.
I'm waiting on my partner to find the compression tester right this second.

Last edited by 924CarreraGTP; 03-15-2017 at 06:51 PM..
Old 03-15-2017, 06:47 PM
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Quote:
Originally Posted by 924CarreraGTP View Post
Otherwise, I have fuel pressure, spark, compression, and I'm going to see if changing the timing will make it tick over.
Justin,
You have fuel pressure, but do you know if fuel is getting past the injectors? Did you clean them? A noid light will show if they are firing, but it doesn't tell you if they are clogged up with varnish and/or corn syrup/ethanol residue.
My understanding is that your engine will fire but not idle when fuel is introduced into the system.(Post #9)?
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Old 03-17-2017, 07:08 AM
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Rich Andrade registered a failure with the LH that would cause a no start issue. The ground circuit was bad. So I'm hopeful this might be one of the problems. I had an idea that the spark module was working correctly because I have two of the EZF, (EZK?) spark modules. Both of them will make the car fire, so I had an idea that the LH was the one that was not working correctly. This is certainly one of the cars problems.
I have done one inconsistent compression test, but I'm going to repeat it because I forgot to drop oil in some of the cylinders, and don't like the tester that I have. All cylinders are running over 80psi. What is good compression and what is bad compression for this engine?
With oil squirted in the back two cylinders they both registered about 137, and 135. Like a said, several of the cylinders did not get oiled. So they run in between 80 and 125psi. I'm not done with the compression testing yet!

Also the spark plugs had gasoline on them so I was getting some fuel spray from the injectors before the LH was sent out. I have not cleaned the injectors yet. I'm fixing to start working on that, but before the LH and EZF were sent for testing the car WOULD NOT tick over even with starting fluid, it would only fire once in a while, and there's a burnt gasoline exhaust smell. Almost like it was only firing on two or three cylinders. It may be?
I'll do a better compression test and report here, but I do know the LH has failed.
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Last edited by 924CarreraGTP; 03-19-2017 at 09:23 PM..
Old 03-19-2017, 06:04 PM
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Here's my basic notes on the compression and which cylinders got oiled for the test, and which ones did not. I just ran out of sunlight today, but all of the cylinders had at least 80 psi. I'm going to squirt some oil in the dry cylinders with low values tomorrow and see if I can get the rings working better. Let me know what you guys think.

I also realized today that the build date is in the car door. It shows 1/84 and I have the name of the original owner who bought the car along with the Dallas shop that federalized it. Oddly the original owner was a native of my hometown. It's hard to believe that someone from where I live had good taste in supercars, and a ****load of money in 1984. I'm now seeking out the original owner for information, but it's a very common name, so I'm not sure I'll find him. 1984 was a long time ago.
I also realized today that the car only has 89,000 miles on it.

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Last edited by 924CarreraGTP; 03-19-2017 at 09:38 PM..
Old 03-19-2017, 09:28 PM
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Justin,
I wouldn't worry too much about your compression numbers yet. The car sitting will allow the rings to get gummed up and not seal completely. Once you start it and run it for while, my experience has been that, with Techroline or another cleaner like B-12 in the fuel, as it runs longer, the rings will start to seal better and better. I don't think your current compression numbers point to bent valves necessarily (if that's what you might have been thinking).
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Old 03-20-2017, 08:48 AM
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I agree with stepson, wait until it is running and test it hot. That said those numbers are pretty bad and even worse they aren't even. It is very similar to the m28/22 motor I bought. It ended up having broken ring lands. If you have bent valves your compression would be almost zero. You could also do a leak down test to see where it going.
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Old 03-20-2017, 03:34 PM
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Leak Down Test -

Hey 924, While you await the return of your computers, as others have suggested you might also perform a "Leak Down Test" to help better determine if you are dealing with a compression issue. Harbor Freight has a leak down gauge kit for around $40 or so. Once you pressurize a cylinder at TDC with 100 Psi, listen for escaping air at the throttle intake (intake valve leak), exhaust tail pipe (exhaust valve leak), with the oil fill cap removed (piston ring leak) and finally with the coolant tank cap off - bubbles, a possible head gasket. The "Leak Down Test" will additionally let you compare the reference air pressure applied to the inlet side of the test manifold to the air pressure being held in the cylinder.

Since you have determined that the spark is OK, if your engine passes this static "Leak Down Test", you'll at least know you are probably chasing a fuel related problem.

Just as some target information - I checked my notes on the compression numbers for a reasonably well running early (185K miles) CIS euro-engine. They were 170, 180, 185, 165, 185, 165, 160, 170. Additionally - a "Leak Down Test" indicated only an avg of 9-11% air loss out of the cylinders. Although all the compression numbers should have been within about 10% of each other - the car still ran out fine.

Please Keep Us Posted - Michael
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Last edited by JK McDonald; 03-20-2017 at 06:22 PM..
Old 03-20-2017, 06:08 PM
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Yes, leak down test is next when I get time. I've got a fever right now and have to get well before doing anymore with the car.
As far as inconsistent numbers on the first compression test, yes the numbers don't match up, but you'll notice on my notes that 1, 4, 7, and 8 were the only cylinders that got oiled. I'm going to repeat the test soon and oil all of the cylinders. Thanks for the advice Stepson, PeteR, and JK McDonald.
Old 03-21-2017, 08:17 AM
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Troubleshooting Results -

Hey 924 - Have you been able to determine the cause of your "No Start" problem ? Many 928 Pelican members try to keep track of the troubleshooting results to help and assist others with similar issues.

Please Keep Us Posted - Michael
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Old 03-26-2017, 03:04 PM
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The LH has been repaired and the MAF sensor was out of calibration. Both EZF units were functioning and nothing was wrong with either of them. The parts are in the mail headed back to me at this time. I haven't had a chance to do a leak down test yet. I'll let you guys know as soon as I get everything plugged back in and hooked up. My fingers are crossed that I might get to the bottom of this issue.
For the time being, how do you guys usually go about getting the main timing cover off? I've always assumed that you have to take the front oil tube off from the oil pan, but last time I did that on one of my 928's I ended up with a stripped bolt and my oil tube constantly leaked until I fixed it with a larger bolt. Do I have to take the coupling off the oil pan? Just wondering what others do.
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Old Yesterday, 06:28 PM
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I few years into the 928 I decided pulling the engine and fixing all the issues was by far the easiest and cheapest route.
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