rben

Thanks for the effort Chrisssssss. Most of the things you suggested i have replaced with new or tested them out, except for the LIM gasket. I think i may have found it. watching the ECM data while driving and some override tests i suspect the TCC is not working correctly. I found an older "string" in here about the TCC solenoid causing a bucking/jerking effect. When i drove it the last couple days i watched and it did the "thing" when TCC was active. Today i did an override and turned it on and off. The second it was on it did the "thing" when it was off it ran just fine. The string mentioned something about putting SeaFoam in the trans. That will be the next thing. If it the solenoid that would explain why all the sensors changed on the engine had no effect on it. Also can anyone tell me/ show me where the solenoid is?

Checked all the plugs and cables, all where good. Took it for a test drive yesterday and it was great.Drove it today and it is doing the thing but not as bad and i now feel it in third gear as well. Watching the the data as it runs. I see the Oxygen sensor feedback, on then off at a "calm" rate of change. Then when it does the jerking/ miss-fire feel it blinks constantly. So either i have a sticking valve or the exhaust has a hole close to the sensor which could be part of the cause.

I can get in to system, not clear on all the data bit i did notice the RPM was at 20 with the engine off. I am trying to find the cause of my rough running in overdrive, and low RPMs. After replacing plug wires, plugs, coil packs, Ignition module, oxygen, cam, and crank senors. Put in a new timing chain, gears, and adjustment magnet. I was working eliminating the ECM from the "cause" list. I checked the feed from TPS, tried 3 MAF units and still the same issue.

EPROM ID 5784

So i potentially have the right ECM with the right chips. Are these chips pre-programmed or do they need to be flashed with the data? If they need a flash then i still have a possibility of it not being right.

Strange, but that last shown ECM, is the one in my car. I see though that the Prom that i have is ANDM not the ANDP. So So checked the TPS and get a good read. Tucked the Oxygen sensor cable down to make sure it does not come anywhere near the rest of the wires. Next thing, to get the exhaust taken care of. It has a leak near the converter so maybe that is causing some issue.es.

Here is an odd question. The ECM has 3 plugs, 2 black and one is orange or red? i got an ECM from a local yard and it was suppose to be the right one (PN:1228253). That was the part number i found searching for a replacement. The one in the car currently is PN:1228786, which is listed as being for the Cadillac Seville. So what model is suppose to be in the car? The 1228253 unit is the orange plug, the 1228786 is a red plug. My car has a red plug. Was there a ECM change? Meanwhile i am not sure how the PN starting with 16 link to the PN 122.

I zip tied the harness up to the engine a while ago while searching for a solution. i will go over it again just to be sure. It is a bit of a shutter at the 50mph at 4th gear when you give it gas. If you give enough gas and it drops back to third it is fine. As for the PROM i am not sure i have been trying everything else before taking on the the ECM. I don't have the tools or the equipment to download or verify the data on the ECM is right. This issue has to be data related somehow. As i mentioned it doesn't do the shutter thing with the MAF unplugged. That tells me the ECM is running a preset program and not using the incoming data with the MAF unplugged. I thought is was the MAF but i have three of them and they all do the same thing. So as for the clutch, other than it running funny would it have other side effects?

It is a 89, and has a fan front driver side, engine side and 1 passenger side, on the out side. The out side one might be for the AC unit. Meanwhile any thought about the ECM and the over drive gear link? I wounder because before the ECM was replaced it did not do the hiccup thing. The shop i took it to, because it died along the road and would not start, replaced the ECM because they said that was why it would not start. So i question if the data that was traversed was all good or all there.

New timing chain, gears, tension-er and cam sensor. It runs, but still has that strange hiccup thing in the fourth gear and only in that gear. So i am wondering if anybody has wiring diagram. I had the ECM replaced, long story, and i wounder if that has something to do with it. At the same time when i try to manually run the 1# cooling fan, It does not work. I found however it does run when fan 2 is on high. With a diagram i my find a wiring issue, i found a few on line but i trust someone here might have better version.

Pretty worn and a crack on the back side. Now i need to get a replacement.

I decided to check in to the cam interrupter, saw it was ..odd. I took a tool to probe the magnet and it stuck to the tool. Then i tried to put it back in...didn't work as planed. So now i replaced the timing change and gears, put in a new interrupter and plan to put it all back together. So here is a question, what is the recommended sealant to use for the cover? Oh, and the chain dampener is really worn.

Well the car is running bad in the loaded state. Replaced the pugs and wires. ran rough for short time with 2 wires in the wrong place but it ran. Straightened that out, but now... it runs with misses with the MAF unplugged but has no issues in final drive gear. with MAF plugged in and final drive it does the spasm thing at low RPMS. So who knows how the ECM controls the system? it seems the data from the MAF is not right or the ECM is not using the data as needed. I figure it must be running close loop with the sensor unplugged. I am running out of... trying to find the cause of its issue. i am almost to the point of selling to highest bidder.

thanks, i have not yet done the plugs or wires, they are on the list. Putting those plugs back on the block is a pain.

Did some testing with the vacuum. When disconnected or plugged off there is a change in how it runs but only for moment then the system adjusts and it is back to "normal". The miss fire acts like my other car with the cap and rotor did till i cleaned up the cap. Being this is electronic control, that cant be done. This would tell me the running issue is more mechanical or electronic feedback related. So, what controls the timing in a low RPM/Idle state? I had the ECM replaced, could there be a programming issue? Or is my cam or crank sensor not quite right?

no, i haven't watched it in the dark. it does do the "miss fire" all the time-ish. just more noticeable at low idle and high gear.I shall test out the cables next. i suspect the vacuum too. i know 2 points in vacuum that are good. only a few more to check out.

An update, changed out the MAS and fuel pressure regulator. runs good at idle mostly. Found a pattern to the issue. It appears to start running like it is missing when in overdrive, RPMs less then 1800, and you give it just enough gas to speed up. Does something change when doing overdrive? it does not appear to do it in other gears. Speed might be part of the equation as well.

I ditched the old Mass some time ago, looks like a trip to the yard in my future. As for the pressure regulator, it is not leaking. i did a pressure check several months ago and had a 40ish pressure then. The ECM was replaced, does PROM data transfer or is it pre-installed in a new one? Mileage, 116055 not a whole lot.

It did at the shop, from January thru end of April while it was being worked on. I have since then filled the tank and put in some injector cleaner, i could add some dryer too.

i never did check the timing chain. the hole in the exhaust is the short piece under the cockpit just after the first 90. It might be close enough to cause some effect. It was running odd again and made note of few things. I runs rough when the rpms are under 2200 and you just give it a little gas. If you give enough get up to speed on a ramp it seems fine. the Idle is a bit rough like a plug is bad, which is possible. I wounder though how does the fuel pressure regulator work, lower pressure at idle, more during acceleration? it might just be good to replace it? Here is another thing, Mass air flow sensor. i replaced it along the way but it seems to run better when it is unplugged. Is it possible i need to calibrate the feed back from the sensor?

padgett, just read -up on your site and see a note of the fans. did you get them to run at a lower temperature setting?

well i currently dont have a way to check the fuel pressure. There is no fuel leaking which would mean the check valve is "ok" but at the same time... if i disconnect the vacuum line to it, here is not change in how it runs. i did however find that it runs better if the Mass flow sensor is unplugged. A side question, what temperature does the cooling fans come on? I found mine run over 200 before kicking in. Plus it is both fans not just one. i tested the relays using the CRT and they come on using "over-ride", one at a time. but when using the output test with "hi" and "Lo", lo does nothing it only runs on high. its almost like the parameters are set wrong or something.

Well few (hundred) dollars later and it runs, mostly. New ECM, ICM, Coil pack, Cam senor, Crank sensor, O2 sensor, and Mass air sensor. So now it runs and sometimes stumbles like it is missing. watching oil pressure and its jumping about even while sitting idle (34-41) psi. This does not seem right, at the same time there is a notable hole in the exhaust. Any of these items make it run like it is missing?

so here is what i have so far. I shot some starting fluid through the air take and it ran for bit. That tells me the spark is good. Then i forced the fuel pump to run but that it did not start. So that still leaves me with a couple things. Are the injectors working? Am i getting fuel pressure? i suspect the injectors first because i could feel and hear noise in the fuel system. So, what controls the injectors?

my thought as well, at the same time figure out why it wont start. checking all the options behind that.