[970 5.0]

So my car is really starting to frustrate me. I had a thread back in april about it acting up every week or so and i thought it was under control but now its happenin more and more. Its a 94 with gt-40 heads e303 cam gt40 U/L intake automatic, 75mm maf t/b and 30lb inj. Replaced the distributor, 160 stat and 255 fuel pump in march/april.

When the car is drivin for 20-45 min at cruising speeds it will start to stall out and the fun begins. As i make my way to the side of the road it still tries to idle but around 200 rpms so i shut it down. I try to start it but it just starts then dies. So i put the hood up turn on my electric fan switch i installed and give it a few hours and limp it home. When i limp it home i have to keep it higher in rpms and my foot on the brakes to keep it alive.
When i start it the next morning it acts perfect. Drove it to work today and pulled the DTCs.

Normally it just has the 332 EGR code as i have it capped.
Now i also have codes 124 - TPS High voltage
& 556 - Fuel pump primary circuit fault.

When it first started acting up i set the voltage to the tps as told by some tutorial i found on here. Is my tps bad? i also read that the 556 could be a bad PCM or CCRM so i pulled my CCRM and checked the resistance between fuel pin (18) and pcm power (24) as told by ALLDATA but the resistance was within the expected ohms.
It doesnt seem to be overheating when it does all this but it does have to be warm for it to happen. It also has been backfiring since it started acting this way when i let off the gas.

Thanks for any help in advance.

[Bubba95SN]

Up your temperature to 180* as 160 keeps ECM pouring fuel (open loop) as it thinks the engine is "cold" Fuel pressure when this car acts up. Do you have spark from ignition cables? Possible PIP inside distributor(stator). More test results needed for proper answer. Advance sells a reman CCRM for about $90.

[ReverendDexter]

160 Thermostat is bunk. Can't say it's the issue, but I'd get rid of it pronto.

[970 5.0]

Well i had a 180 in before and the problem was there. i went down to 160 to make the car run cooler thinking it was some kind of overheating problem. Ill switch back to a 180 but i dont think the 160 is making my problem unless maybe my old stat was bad as well?

[970 5.0]

i do have spark on the cables. its a little hard to test on the side of the road but when i pull a plug and lay it on the strut tower it sparks until it dies which is a second or two. I had a bad stator in my old dizzy thats why i got a new one.. is there a test to try for the distributor or should i just try to return it it is under warranty i think

[Bubba95SN]

Warranty still good.....return that part.

[970 5.0]

okay so yesterday i reset the voltage to my tps and decided to time my dizzy again just to make sure it was right. i set the base to 14* and it felt like it was running rough. plugged the spout back in and watched the timing with the spout in and it jumping timing like crazy. anywhere from maybe 5* under tdc to 20ish or more over. just at an idle. any ideas why this is happening?

[ReverendDexter]

Isn't stock timing like 8*? I'd try setting it there before I advanced it.

[970 5.0]

I did set it back down to 8, but that doesnt tell me why its jumping around at an idle it is doing it at any base timing with the spout in. I found that around 10* is the best driveability for the way its running. seems if i drive it with the spout out it doesnt act as bad

[mustangtommy]

more than likely the sensor on the side of the dizzy is bad, mine use to do that same thing till i replaced the sensor

[970 5.0]

Is there a chance my ACT sensor in my intake is bad?? I read it has a lot to do with afrs and timing curve...

[970 5.0]

bump on the ACT sensor. Anyone have experience of these going out? I know theres a voltage test but i dont want to drive around till it acts ups to test it..

[95opal]

Originally Posted by 970 5.0 I did set it back down to 8, but that doesnt tell me why its jumping around at an idle it is doing it at any base timing with the spout in. I found that around 10* is the best driveability for the way its running. seems if i drive it with the spout out it doesnt act as bad

When you pull the spout out it locks the timing so you can set your base timing. Once you put the spout in the ecm takes over and will advance and retard according to the data it recieves from the engine sensors. It seems as everything in that aspect is working properly. If this only happens when the car is warm I would look at the TFI module as being the culprit.

[91cobra5.0]

Originally Posted by 95opal When you pull the spout out it locks the timing so you can set your base timing. Once you put the spout in the ecm takes over and will advance and retard according to the data it recieves from the engine sensors. It seems as everything in that aspect is working properly. If this only happens when the car is warm I would look at the TFI module as being the culprit.

+1 good news is that your local autozone can test those but make sure the person using the testing machine knows what they are doing cuz i was chasing a idle issue a whle back on my fox and the guy tried to tell my my tfi was bad and i had him test the new one.. turned out the guy didnt know wtf he was doing

[970 5.0]

well i just didnt think it should jump around that far... i have it set at 12* now took it for a drive yesterday and all was good for bout a half hour then i was slowing down for a light and when i went to go... nothin.. pulled over and cranked it for a little and it started and i was able to get it back home. The tfi module is the one under myCAI right? is there anyway to test it myself?

[970 5.0]

had the TFI tested and it passed.. a million and a half times lol
maybe its time to buy a bad ass distributor?

[970 5.0]

had the TFI tested and it passed.. a million and a half times lol
maybe its time to buy a bad ass distributor?

[mustangtommy]

ya i guess its time to get a new dizzy