cjonesmo

Hello to everyone. I have a 1986 NA 944 - just for clarity's sake. It sat for a number of years before I went back to get it running - long story short, I replaced everything (fuel pump, injectors, dme relay, dme, etc..) - and was finally replacing the speed and reference sensors (yes the speed sensor was bad - but didn't figure that out until I replaced the tdc). - anyway ...

I had a stuck speed sensor, could NOT get it out and couldn't get the drivers (lock) bolt out of the bracket. I FINALLY but the bullet and ordered a new bracket and broke the old one out - but the allen head stripped on the (drivers side) lock bolt. I tried the T40 torx trick and rounded the inside even more. Then moved on to (small) vice grips and have a severely rounded bolt head (inside and out). I've also tried cutting a notch with a dremel - no dice - stuck in there like it was welded on. At this point, I think I need to cut off the bolt head and drill it out with a dremel or flexible shaft for a real drill - possibly with left hand bits (in hopes in comes out). I'm not inclined to use easy outs since I hear they can break and make a bad situation worse.

I've been working this for about 3 weeks now and am starting to really hate this car.

I'm considering calling a mobile mechanic as a last ditch before the cutting and drilling begins - but thought I'd check here one last time for any final advice. I've read every board and forum post related to this from here, clarks, pellican, and more. Any final words of advice are appreciated. I have not YET tried anything with a torch....but I'm thinking about it.

cjonesmo

Well - since no-one replied, I'm assuming that no-one had better advice than drilling it out from the back. At this point I pulled the intake and the Air Oil Seperator (Oil Filler Neck/Tube). I tried several more times with all of this out of the way and it still won't budge a millimeter. I think I can get to this with a right angle drill from the back to drill it out. I guess I'll have to write this one off to learning every bolt on the car. Maybe it will run next week.

cjonesmo

Finally drilled out the bolt from the backside with a right angle drill. Re-installed the bracket, sensors, manifold, AOS, and it still won't start....maybe the sensor gap is wrong - still fighting with it. So far have replaced Fuel Pump, Fuel Filter, Injectors, Speed/Ref Sensors, plugs, DME, DME Relay...the injectors spray fuel and it has spark.

Grandpa#3

When attempting to start, If the TAC Needle jumps about 1/16" the Sensor is set right. NO jump reset the Speed Sensor. I have used a new Sensor and glued a doubled piece of Match Book Cover to end of sensor. No need to remove as the paper will get buzzed off.

Cheers,
Larry

cjonesmo

Thanks for the info. The tach does bounce, but mich higher - bouncing up around 2-4k - so maybe it's still not gapped right. I glued a small piece of cardboard to the bottom of the speed sensor, so I thought it was right - but perhaps not - I'll pull them again and reset.

peanut

looks like you've had some real bad luck with the sensor .Its a pity you didn't do a thorough search of the site as this problem has been tackled a thousand times before in fine detail with lots of helpful threads.

Its always best to tackle 'no-start' situations by systematic checking and testing rather than mass replacement of parts until something works however provided the new parts have been tested as working it can't hurt .

I presume that you have no fuel delivery to the inlet manifold ? and you have no spark at the plugs ? is that right ?

You give us no idea what is working and what is not , nor do you tell us what you have tested so forgive me if the following covers things you have already done but I have to start at the beginning.

Check the engine is cranking at 225rpm minimum or the ECU (engine control unit) will prevent the fuel pump running and the ignition system from working . (its a safety feature.) count the engine revolutions for 5 seconds and multiply by x12 will give the revs per minute

Remove the DME relay
With ignition off
Check you have 12v+ at terminal 30 on the DME relay socket .
Check that terminal 85 on DME relay socket is earthed
Replace DME relay Switch ignition on
check 12v+ at injector electrical connectors
Check fuel pump fuse (fuse No 34 ?)
Crank engine 12-15+ turns
check you have 12v+ at fuse 34 when cranking.
check you have a spark at the spark plugs
check you have fuel on the spark plugs

If you still have no spark or fuel then fit a 3x way bypass cable in place of the DME relay and try again.
The 3x way bypass is simply 3x pieces of insulated electrical wire joined together. One wire goes in terminal 87 the second wire goes in terminal 87b the third wire goes in terminal 30 .

Once connected it should force the ECU to run the fuel pump continually and also force the ECU to pulse the ignition system to produce a spark.
See Clarkes Garage Workshop guide under DME relay
http://www.google.co.uk/url?sa=t&rct...gDBWWj0KT9tcLA

cjonesmo

I did pretty extensive testing and at this point, I DO have spark (tested with spark tester on each plug wire) - and I replaced the old plugs too just to be safe.

I also DO have fuel - pulled the fuel rail and get a decent spray from all 4 injectors now.

I still need to try to re-gap those sensors to be safe, but probably also need to do a compression test at this point to be sure that there's not something more serious going on. I can see the timing belt through the cam tdc hole, so I don't think it's broken.

I have tried with the (replacement) DME in as well as jumpered, but it doesn't seem to make a difference.

peanut

ok thats better information .

When you say it makes 'no difference' when you fit the 3x way bypass I take it that the fuel pump runs continuously with the 3x way bypass in place yes ?????

You have a spark at the plugs and you have fuel from the injectors .

Has the engine attempted to start at any time ? has it coughed or backfired or anything ?

I can only suggest that you check the cam belt is not broke or wrongly fitted because all you need is fuel ,compression and a spark at the right time for an engine to fire.

Have you tried spraying 'easy start' in the inlet whilst cranking ?

Have you tested the sensors are supplying data to the ECU ? You need to disconnect the small electrical connector next to the ECU connector and measure the impedance of reference and the speed sensor.
Speed sensor terminals 8 & 27 should be 600-1600 ohms and the same impedance 600-1600 for the reference sensor between terminals 25 & 26 .

Don't connect the multimeter to any of the connector terminals on any of the connectors going into the ECU only the connectors coming from the wiring loom

cjonesmo

Finally got it back together and the sensors correctly gapped (I think) - and it sounds like it's TRYING to start now - it ALMOST starts after several tries. I pulled the coil wire to check it and it came apart, so I'll replace it today - even though each spark plug wire showed a spark, injectors were firing and had fuel coming out when I pulled the rail.

Compression WAS a bit low when I checked it - around 120, but I think it should start up - I'm going to replace the coil wire today and next week have the fuel injectors rebuilt locally ($25 each) - and give it one more go.

Appreciate all the comments and help though - it's kept me motivated to get her running - even though it sounds like I probably need new piston rings - I'm just not quite ready to tear it apart for that.

peanut

compression at 120psi is fine thats not the problem.
if she hasn't started for a while there are a number of things you can do to improve the odds.
1. renew spark plugs or file the electrodes to a nice clean sharp edge . Electric sparks prefer a nice sharp clean edge .( i actually pre-heated my plugs in the oven because it was winter )
2. Clean all the hi-tension connections. Just pulling the connectors off and replacing will make a better connection.
3. Clean the electodes on the distributor cap, again if you carefully file the electrode edges to a sharp edge it will improve sparking.
4. If you cannot hear all your injectors clicking then the solenoids are probably sticky. Disconnect the electrical connectors and use a 9vDC PP3 torch battery and some wire and touch the battery leads on the injector terminals 20-30 times until you can hear the injector solenoids clearly clicking back and forth.

lastly you could attach another battery to make sure the engine is turning over quickly and clean all the earthing points particularly the battery, starter motor, and engine to bulkhead points.

You could also try towing the car to bump start it .oh and I forgot you could try some ' easy start' in the intake
good luck.

cjonesmo

Ok - finally back after this one. At one point I had it starting with starter fluid and it backfired and blew the boot off. I figured that the new injectors probably got clogged by something - some weren't spraying, so I replaced them again. I've also since replaced the plug wires and put in an MSD Blaster 2 coil.

So at this point, I will start over to verify spark, fuel, compression from scratch and let you guys know what happens. Is it possible I bent the valves or something when it backfired?

peanut

if you have a good strong spark at the plugs and fuel to the cylinders you are there. The only things that are likely be causing a problem now is mis-timing or poor earths , shorting etc causing weak or intermittant electrical performance .

The backfiring suggests that you have a poor spark and the starter fuel built up and eventually ignited in the exhaust .Its very volatile stuff.

No you wouldn't have bent a valve or your engine probably wouldn't turn over.

Have you tried towing the car and bump starting it ?
have you actually done all the things that I suggested in my previous post ?

You may think my suggestions aren't applicable but I've had this situation twice myself and resolved it both times by doing the things I suggested.

So far in this thread I've spent a considerable amount of time trying to help you and you have completely ignored all of my suggestions and have not answered a single question or acknowledged trying a single suggestion.
If I don't get some answers this time I'm afraid I shall not be able to help you further sorry.

cjonesmo

Sorry Peanut. I'll try to be more clear in my posts, but I believe that I've tested everything electrical that you had suggested.

Let me be clear. I have tested all of the voltages to the DME and at the ECU connector. When I jumper the DME, the fuel pump does run continuously; however, with the DME in, I do get spark, fuel, and tach bounce (spark verified by pulling spark plugs and grounding while cranking, fuel verified by pulling fuel rail and watching spray). At the point, the following are new - fuel pump and filter, fuel injectors, speed/ref sensors, coil, distributor cap, rotor, sparkplug wires, and sparkplugs.

I don't want to waste your time and do appreciate your advice and help here.

I agree that it could be timing. I don't think it's a grounding or electrical issue at this point since the plugs are firing. I pulled the timing belt cover and the belt is intact, but maybe it slipped. I'll try to verify TDC tonight.

It sounds like it's firing on one cylinder when I try to start it so maybe that's the problem. It will not start with starter fluid. I had to pull the intake manifold to drill out the sensor. Is it possible that I hooked anything else up wrong when I did that? I did replace the gasket and was careful to ensure that gasket was on correctly (not backward) and was aligned well.

peanut

there is another example of not providing critical information ! How do you suppose that anyone is going to help you from the other side of the world who has never seen your car or you and knows nothing about the car and is totally dependant on what you deem important enough to tell us ?