Robby

X-posted from regular 944 board, but since I think it's possible it could be KLR related, I'm posting here too- not to mention my desperation....


Ok- car's been down most of 2yrs- in mid '07 I was driving along, relatively slowly- accelerated gently, uphill- engine cut out, ready to die- I lifted & it idled again- I accelerated & it cut out again & so on, untill I slowed to a complete stop. Thought it was a vaccum issue, then IC hoses popping off, plug wires, dist cap, rotor button, etc- went through all of that. Had engine rebuilt due to mileage, etc (180k)- Tom C built it & the turbo & also resurfaced FW, etc- my mech put it all in.

So, here we are now- car was started some of the time, after the rebuild, but my mech didn't hook a LOT of things up, so I slowly went through it & the car sat most of time, not running. When it did start, they were hard starts, rough idle, loud, etc, but sometimes would NOT start at all & definitely not at all now.

I was getting no spark at the starter coil. I THOUGHT it was the KLR- we checked the DME & KLR, etc & then I swapped out the KLR & it started right up. A few weeks later, it would NOT start again. So I swapped in ANOTHER KLR & car started right up, but here we are, several weeks later & it will NOT start again. So the other day, I bought a new starter coil (still no spark at the coil). I checked the cap & rotor, etc- new plug wires- new sensors, newly refinished FW, etc, etc... But after the new starter coil, STILL, NO START!

Any ideas? Any help would be greatly appreciated. Not sure what I could offer, but I'm at the end of my rope here & would gladly do something for whomever would get me up & running... Even some $, although I'm not exactly liquid at the moment, but I could offer a little... Please help- I've put so much into this thing that I hate to let it go for something like this, but this is killing me....

thanks a lot,
Robby

fast951

Hi Robby, When you accelerate, you are activating the TPS, the AFM is moving and of course the air is going through the intake. Reading the first part of your description, I'm thinking a vacuum leak. However, since you already checked the intake system. I would say check the TPS and the signal from the AFM.
Can you rev the engine without a load? If so, it may not be the TPS (unless the TPS acts up when it gets hot). Next, put a voltmeter on DME #7 and monitor the AFM voltage.
Any chance you can check the fuel pressure??
Have you checked ALL of your ground connections (firewall, bellhousing,..)?



Is the engine turning but not firing? Or not turning at all? Why did you replace the starter?
It will help greatly if you can isolate the problem. So far changing KLRs got it to run for a while, then stopped running again. Was the original KLR bad, then the 2nd KLR went bad? Or there is something else causing all of this, like a wiring issue? (You move the wires when you remove/install the KLR).
For testing only, you can take the KLR out of the loop. Disconnect the KLR, jumper on the KLR connector pin #9 to pin #16. See if the car fires, if it does, there is a problem with the KLR. If it does not, it's not the KLR.
(The above test is just for testing, do not drive the car!!!!).

For the engine to run, you need the followings: Compression, Fuel and Ignition Which of the 3 are you missing??

Robby

Thank you for your reply John- I really appreciate it. As for part #1- I'm really not sure if I could rev it w/out load. Being so long ago, I don't remember trying, but wish I'd thought of that & if it happens again, I will.

I thought about the TPS too- I changed it back in 2000 (bought car in 99) after some intermittent boosting issues & it cured that prob. Anyway, after the rebuild & all that's gone on the last 2yrs, I've had the car started & have driven it around ~7 or 8 miles total over 3 or 4 total times It felt like it was going to die each time- ran very rough & while it didn't cut out under acceleration like before, it did eventually idle so rough & low, that it died. I rebuilt the TB & made several little adjustments, but it still idled poorly. I was hoping that this was partly due to having sat for so long & that it just needed to be driven a little bit, but the last few times I've been out & tried, it has not started at all.

It cranks strongly, but will not actually start. The battery seems fine & the starter seems fine- I replaced the starter coil b/c the last few times I've checked (during no-start) it was getting no spark. The starter itself seems fine.

RE KLR test- THANKS for mentioning this- I did this test for several KLRs awhile back- on one of them, the car DID start when jumping the pins. On another KLR, the car did not. And I'm pretty sure, that w/a 3rd one, it did start once & did NOT start a few times too. I thought the car was SUPPOSED to start when you jumped the pins, but you're saying it's NOT supposed to start...? I have the jumper & will try again.

Seeing that I'm getting no spark, I think it's ignition related & I'm afraid it could be wiring to the KLR or something- PITFA to trace &/or fix. I'm even wondering if going stand alone would be a way to bypass the factory wiring, thereby eliminating any bad wiring to KLR (or DME)...? Maybe a pricey way to do it, but at least it might be a nice mod to have out of it...?

thanks again

fast951

Robby, You need to have the KLR box disconnected when you jumper the pins.

Have you changed fuel filter? Is your fuel pump flowing enough? Have you checked fuel pressure? Speed & Ref sensors? You need to check all the basic items first!

So far you have not isolated the cause of the problem. So replacing parts or jumping to a standalone is a premature decision.

hp18racer

I got the symptoms you describe, harder and harder to start, rough, low idle then finally no start at all when the bolt that holds the cam gear to the cam shaft came loose.

Have you done a compression test since it went to no-start?

fast951

hp18racer brings a good point. Make sure the distributor cap & rotor are fine. Is the rotor & nut well connected (not sliding all over?)

hp18racer

If you are sure there is no spark, does the tachometer bounce when cranking? If not this says the computer doesn't see the engine turning. Can you get an o-scope to check the crank/speed sensor signals? If these look good, have you tried hot wiring the + side of the coil to 12V to rule out a problem with the ignition switch?

How about testing the path to ground the coil through the KLR? Zero resistance from the coil to the plug on the computer end of the wire harness? Zero resistance from the ground points in the wire harness to the bell housing?

Took me a couple of hours to test all this on my car with wire diagrams in hand, a lot easier than doing a complete engine management system...

Robby

"Robby, You need to have the KLR box disconnected when you jumper the pins."

YES, I knew that- I had forgotten!!! It has been months since I tried this & I didn't really understand what I was doing (I stilll don't fully get it). But I will try again. You see, we were pretty sure the original KLR was bad. We had removed the DME & swapped w/another 951 DME- no start. Then we swapped his coil in- no start. BOTH of my pieces started HIS 951, so he had given up & I said: "well, we've got it all out, so why not try the KLR too?" He didn't think it would do it, but we tried it & my car started right up. So we were pretty sure my original KLR was bad.

I got another KLR & the car started, but only a few times- I did the KLR test at that time. I can't remember how it all went, BUT I did the test a few times as it was sort of an intermittent no-start situation. SO, I got a 3rd KLR & used it- car started up a few times & would not a few times, etc. I've tried maybe 20 times this last week, to no avail. So this was/is making me wonder if it could possibly be a wiring issue of some sort. BTW- I even carefully cleaned out all of the contacts of the big plug that the KLR plugs into...

"Have you changed fuel filter?"

Yes, it is new.


"Is your fuel pump flowing enough? Have you checked fuel pressure?"

It appears to be flowing enough, but that would be one to test- I can't answer that one & I know nothing about the pressure- yet.


"Speed & Ref sensors?"

Yes- they were replaced when I did the newly resurfaced FW & my mech has always been pretty big on these items- I had a bad one years ago & went w/it for a long time. But they are good now.


"You need to check all the basic items first!"

Looks like I need to do a little homework here. I'll find a way to check fuel pressure, etc.


I DID check the dist cap & rotor button the other day & all appeared fine- both are very new w/new magencor wires.

hp18racer - I have not tried a comp test, but I'm thinking it would be good w/a newly rebuilt motor- the motor has maybe 30 miles on it, but then, MAYBE that's something to check... Interesting about the cam gear bolt- I'll check that tommorrow or Monday when I'm out there.

Thanks again guys!

Robby

"...does the tachometer bounce when cranking?"

It did not, before the new sensors, but then, I have not thought to check since the new ones were installed. I will though- thanks for reminding me of this...


"Can you get an o-scope to check the crank/speed sensor signals?"

Someone just mentioned that yesterday- I'm not sure, but might have a way to get the car to someone who does have one & CAN check... Sounds like this might be neccessary, but first, I WILL check the tach.


"...have you tried hot wiring the + side of the coil to 12V to rule out a problem with the ignition switch?"

No- thanks for the idea!!!


"How about testing the path to ground the coil through the KLR? Zero resistance from the coil to the plug on the computer end of the wire harness? Zero resistance from the ground points in the wire harness to the bell housing? Took me a couple of hours to test all this on my car with wire diagrams in hand, a lot easier than doing a complete engine management system... "

Ok, I'll need to reread this one a few times just to understand it (I admit that I'm an electrical idiot). I can get the wiring diagrams. You guys are giving me some great stuff to try, at least. I knew when I posted that I needed to narrow down some stuff...


Thanks again!

hp18racer

With the cam gear bolt not tight I got 50lb on a motor that had shown 150lb the week before.
New speed/crank sensors can be improperly adjusted or have a shim they shouldn't a good sensor doesn't necessarily mean a good signal to the computer.

John probably has better advice than I do, I'm an amateur. I do understand your frustration having worked through similarly confounding problems myself.

Good luck!

Robby

hp18racer- in an e-mail version of your reply, you said that you had plug wires that had fouled so bad, due to a bad TPS, that it caused a no-start...? I did replace the plugs w/the wires, cap, button, etc, but I guess this is possible. But IF they are fouled, they did it FAST!!! Could the TPS make them foul THAT fast, so that w/in 30 miles of driving & less than one hour of idling, they could actually be fouled to that extent? Man, I wish it was as simple as a new TPS... That's cheaper than the new coil I bought. A wasted $103 that was...

EDIT-
Yes, John is an electrical genius- I'm just hoping that anything he comes up with, he'll be able to dumb-down enough for me to grasp on some level. I really am electrically challenged. But yes, it is frustrating to no end & I thank you (& anyone else) for offering any advice / things to try. I know there are enough of these cars on RL that someone could relate some similar experience that might help. That cam gear bolt could very well be a possibility. Looks like I've got quite a few things to try, so far...

944Fest (aka Dan P)

IF the cam sensors aren't adjusted just right, you can get an intermittant no-start when the battery is low. low batt, crank, no tach bounce. Well charged batt, crank, tach bounce=ignition. MAke sure that tach is hopping when you crank!

hp18racer

I had plugs foul on me due to a bad TPS, took several hours of driving to get that way. Problem is that the car thought it was either at idle or at WOT. Any time spent at partial throttle was very rich and fouling plugs.

With KLR swaps making it sometimes work, sometimes not, I'd be looking for resistance in the wires relevant to firing the coil and at the crank sensors as the most likely suspects.

quinnfiske

Have you checked the DME relay in the fuse/relay compartment? It is G5. It enables the DME and fuel pump. When they fail, the engine cranks but you get no spark and/or fuel. Clark's Garage has a proceedure for making a 3 way jumper to bypass it.

Do you have the factory alarm? When armed, they disable the DME relay. They can do the same when they fail. It is a box about the size of a pack of cigarettes on the bracet that holds the DME/KLR. You can unplug the connector and jumper past it. Clark's has the details also.

Robby

Just got home from work (15hrs)- thanks for all of the input- I love this place! And while I haven't been gone completely, I have been around a LOT less these last 2yrs...

Great to see some familiar faces still around- like you Dan- hope that unique glacier blue baby of your's is holding up well... I'll definitely check the tach next time I try- Monday at latest... Cam sensors? These are the same as reference/speed sensors, right...? If so, I'm pretty sure they're adjusted right (for several reasons). I'm less than 1wk from having it towed to a mech, so I will check the handful of ideas that are being given to me here that I can try myself & IF none work, then I will certainly have the sensors checked by a mech. It's a good possibility, at this point....

hp18racer- I think the 2nd part of your last reply is an excellent point.

quinnfiske- Excellent ideas & very likely suspects, so thanks for mentioning, but, I do have a new relay- was one of the first things I did- already had a spare- ended up buying two new ones- tried both- then a friend did the relay jumper test & they checked out fine... And, I do not have a factory alarm.



Thanks again everyone!!!