Missing and stalling Reply #15 – May 08, 2012, 03:15:46 PM That is insane fuel consumption....... maybe injector hanging open? Quote Selected
Missing and stalling Reply #16 – May 08, 2012, 05:41:35 PM What dos the map sensor read voltage wise at idle? There is a way to test its output based on vac pressure.If your fuel pressure was cruddy, the o2's should throw a code. If the map sensor is bad, it goes into a fail safe (limp mode) and should also throw a code. If you have the ability to read fuel pressure, it would be a good idea too.If you have a bad leak in your vac line to the map sensor, you'll get about 5mpg and leave black soot under the tail pipe, staining the ground. Quote Selected
Missing and stalling Reply #17 – May 09, 2012, 12:58:58 AM I got some more time to putter around with it tonight, and there is a huge miss visible on the timing light right off the coil with the SPOUT in and warmed up. When it's cool, or when the SPOUT is out, there is no discernible gap in the light, so it at least is producing enough spark to trigger the timing light then. What exactly does that point to? I suppose the PIP should be ok, because it's output isn't SPOUT dependent, so most likely a TFI module that goes bad with heat? They tested ok with the Ohmmeter, but that was when they were cold. They're both aftermarket too, so it's possible they could have failed in a manner that I'm not familiar with. I don't have a fuel pressure gauge yet, but I did unhook the fuel return and blew through it with some very low air pressure from my compressor, it bubbled in the tank quickly, so there's not likely to be a problem there. Just a theory that was fairly easy to check. As for possible vacuum leaks, I got a strong reading of 20in at idle at both the brake booster and the MAP sensor. I didn't test voltage at the MAP because I read that its signal is a frequency signal, and my meter can't read frequencies. Quote Selected
Missing and stalling Reply #18 – May 09, 2012, 01:01:23 AM Quote from: mcb82gt;389383That is insane fuel consumption....... maybe injector hanging open? That is entirely possible. I'm guessing that I have a multiple cause problem here, it has sit for a long time, which is why the mileage is so low, but it's also possible to have varnish build up in the fuel system. I'm running some injector cleaner through it, but it probably won't help very quickly. I'm not too worried about the injectors though, I'm planning an HO (or similar) swap. Quote Selected
Missing and stalling Reply #19 – May 09, 2012, 01:42:19 AM Get the car to operating temperature -- when your issue starts -- and shut it off. Disconnect the o2 sensor harness from the engine harness. Restart and let it run for a few minutes.....What happens? Quote Selected
Missing and stalling Reply #20 – May 09, 2012, 03:45:09 AM Well, I'm not sure where to go from there. I don't know enough about what changes are ddone spout in or out to tell even what sensors are being used. The computer will turn off adaptive strategy with the spout out. It has to be caused at least partially by the output of a sensor if it runs fine cold/spout out. Electronics fail much easier when there warm. Autozone will test the tfi, but make sure they run it a couple times, to get it warm.Try unhooking the o2's like paul mentioned. Quote Selected
Missing and stalling Reply #21 – May 09, 2012, 03:56:31 AM Have you checked ground resistace betwee block and neg post? How about sigrtn and neg post? A bad ground to the eec could trip up certain sensors, giving the computer odd spikes. A weak ground acts just like bad or overheating electronics. As the load becomes too much for the ground, it will start to lose continuity, then that can releive some of the load on the wire, giving it a weird random almost on off stumble. Quote Selected
Missing and stalling Reply #22 – May 10, 2012, 08:26:11 AM Looks like the missing isn't completely temperature dependent. I started it up yesterday, and it was missing from the coil right away. I let it run until it eventually stalled, then I tested the TFI again to see if it failed when hot. All tests were exactly the same as when it was cold, so TFI can probably be ruled out.After that, I went around and removed and cleaned all the grounds I could find, including the computer ground in the kick panel. After that, I started it up again, and while it still wasn't running perfectly, the timing light showed absolutely no missing at the coil, even after I took it for a 15 min drive to make sure it was completely warmed up. Then, unhooked the O2 sensors to see what would happen. No check engine light came on (I didn't check the codes afterwards though), and while it seemed to run a little bit worse, it didn't run any better when I pluged the 02 sensors back in. I hooked up the timing light again, and I found the missing was back. When I hooked the TFI back up after the test, I messed with the wiring a little bit, and then I had to tug on the wiring a bit again when I unplugged the O2 sensors, so I'm thinking I might have a problem in the wiring behind the upper intake there. I'm thinking the PO had the upper intake off for some reason, so it's possible he accidentially crushed a wire or something back there. I think the only real way to check is to take the intake off again and look at those wires closely. Quote Selected
Missing and stalling Reply #23 – May 13, 2012, 01:57:40 PM Yea Joe! I have nothing to contribute to this thread except to say I'm glad you are here and posting. Hope you get this sorted.For everyone else, Joe and I went to college together and he even helped me wrench on the old cat a few times. I still remember changing the water pump…with the assistance of a dental pick found in the front air dam. Good times. Quote Selected
Missing and stalling Reply #24 – May 15, 2012, 02:37:54 PM I have no idea why there was a dental pick in your air dam, and I have even less of a clue why it was so helpful for us, but I do know we couldn't have changed the water pump without it. One of the strangest car repair stories I've ever experienced. Pretty trustworthy, that SSX, but at least we did end up repairing his Cougar. (It was a sweet car too.)No updates on my Thunderbird yet, the Wife and I were out of town all weekend, so I didn't get a chance to do anything. Not sure if I have time to remove the upper intake tonight, but I'll poke around in the wiring harness to see if I can make it change moods. Quote Selected
Missing and stalling Reply #25 – May 15, 2012, 03:31:23 PM Let us know what happends. I hope we can all learn from this. Quote Selected
Missing and stalling Reply #26 – May 16, 2012, 01:14:42 PM Quote from: Haystack;390020Let us know what happends. I hope we can all learn from this. I'll be sure to post the culprit when I find it, I'm always annoyed when I'm searching for similar symptoms and they never tell what fixed it. Just stopping to think now... The spark seems to be a major part of the problem (probably not the entire problem though, but let's start somewhere.) The only things that really control the spark are the PIP, TFI module, computer, coil, and all the wiring in between. Now, the problem is somewhat temperature dependent, it gets worse when the engine warms up. So, it seems unlikely that it is the computer, as it doesn't get any of the heat from the engine bay. The PIP and TFI don't seem very likely, as I have swapped them for a different set. There's no guarantee that either set is good, it seems unlikely that both have failed in the same hard to detect manner. As for the wiring, it seemed like all my poking and moving of the wiring last night made no change. If it was an intermediate short, I think I would have had some effect. That just leaves the coil, which seemed to test a little weak during the "no spark" testing. It also is subjected to engine heat and wouldn't be affected by manipulating the wiring. I measured the resistance over lunch, and I'm getting 0.3 on the primary and 8 kohm on the secondary, which is right on the low end of what's acceptable (according to the specs I could find). When I get a chance, I'll check it when it's warm to see if that makes a difference, or I could take it to a advance or oreilly's to see if they'd test it. Quote Selected
Missing and stalling Reply #27 – May 16, 2012, 01:50:44 PM Joe , Please check your pm I sent you friend. :poke:p.s. my :2c: worth Quote Selected
Missing and stalling Reply #28 – May 16, 2012, 02:40:51 PM I have a spare EEC that you are welcome to try to rule out the computer as a suspect. Quote Selected
Missing and stalling Reply #29 – May 16, 2012, 05:08:29 PM Quote from: Loaded87IROC;390068I have a spare EEC that you are welcome to try to rule out the computer as a suspect. I'm going to get a new coil tonight, but if that doesn't work, I'll take you up on your generosity. Thanks for the offer. Quote Selected
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