Hi folks need a little help I have a 1990 tbi 318 in a w150. Truck ran great with no issues got yanking on a log pretty good and since then the truck starts and idles fine but after about 5 or 10 miles it pops through the throttle body and dies out. Starts right back up every time. when the issue first started I could feather the gas some and it would smooth out now it seems to be getting worse. No noticeable broken wires or disconected plugs. can the torque converter lockup solenoid cause this? truck is reading a code for that. no thermostat in the truck someone else suggested the coolant sensor is that possible. also the cap and rotor had some carbon built up scraped it off no change. spark looks orange not the pretty blue i'd like to see. new plugs and wires didn't help at all either. new fuel pump, sending unit and filter. nothing seems to help any ideas?

 

Torque converter lockup solenoid. The first thing you need to do is to find out if you even have it. I have had that code forever but I do not have that system.

If there is carbon on the rotor and cap replace them. Cleaning plugs, cap, and rotor are not recommended in any computerized vehicle. The color of the spark is not a good diagnostic tool in our computerized trucks.

The coolant temp sensor usually fails completely or goes out of spec. It usually doesn't give an intermittent problem but it can be checked.

Since this problem seems to have surfaced after aggressive log pulling I might suspect a possible timing chain/gear problem. This would explain the intermittent problem and the fact that it is getting worse. Have you checked the timing?

I always look at the injector spray pattern first because it is cheap and easy to diagnose and the symptoms you are describing can be early warning signs of sticking injector. Look down in the throat of the throttle body to check the injector spray pattern. There should be a fine cone of atomized fuel at the base of each injector that reaches the sides of the throttle body with no gaps or streams. Low ambient light and a flashlight helps to show off the fuel cones easier.

 

Thanks for the info. definitely going to replace the cap and rotor probably the coil to since it's less than 20 bucks for oem replacement. How can I tell if the truck has the torque converter lock up. haven't checked the timing yet but that's now on my to do list. I thought briefly that it could be a timing issue but dismissed it because I figured it would be acting up all the time or give me trouble starting. I'll check it anyway. I've worked on a lot of the older big blocks and usually a orange or yellow spark was a weak one. Last time I took it out i could hear a spark knock going up hills just before it died. wasn't doing that before.

 

Here you can find the sum knowledge about the torque converter lockup solenoid that exists here on the forum. Not much. I have never seen one on a 1st Gen but I am told they were used in the A500 90-95.

https://dodgeforum.com/forum/1st-gen...-solenoid.html

https://dodgeforum.com/forum/1st-gen...e-driving.html

 

Thanks for the link. Not sure what transmission I have the part # pk4505154. I tried looking up the numbers but couldn't find a whole lot. There's 3 relay's on the driver's fender. On the transmission itself there are two wiring harnesses one is a three wire pretty sure that's the neutral safety. and one above it thats a two wire. It has a push button overdrive which I did not realize because it was pushed through the instrument panel before I got the truck. I put a timing light on it the emissions label says 10 btc. It looks to be about 2 degrees off. Also i checked the injector spray. It looks like good cones on both injectors but if i hold the throttle steady around 2500 3000 rpm the injectors both cut out intermittently. Is this normal. Thanks for your patience I love this truck and really want to figure out the problem before it causes any major damage.

 

You have an a518 trans with no lock-up..the code is just a "phantom" code...don't worry about it.

As for your timing did you check it with the engine warmed up and with the CTS disconnected as per the manual?

did you put a thermostat back in it? If not put 1 in it, the correct one (192-195 degree) then recheck your timing and how it runs...a FI vehicle has to run at the correct operating temp or it will have all kinds of weird problems.

You also say the spark looks weak...did you check the coil or replace it?

 

Yes checked the timing with the engine warm and the cts unhooked and the timing was about 8 degrees atc with the cts hooked back up it was at 8 degrees btc thanks for the trans info.

 

going to put a new t-stat in tomorrow and replace the cap coil and rotor as well recheck the timing and see if there's any difference

 

forgot to mention that a couple of months ago the catylytic converter plugged so bad the truck wouldn't run so i cut it off and replaced it with a piece of pipe. It ran fine for a while until recently.

 

replaced cap coil and rotor and t-stat. no difference so I checked the engine codes and now I'm getting codes for the coolant temp sensor and the automatic shutdown relay. checked the resistance of the temp sensor and it's not within the specs the book describes same with the asd relay. going to replace them both and see if that helps. the code for the temp sensor says the voltage is either too high or to low and the code for the asd says it was triggered because the voltage was below 11.75 volts. I did check the battery voltage coming in to the asd and it read at 12.5 volts should I be looking for a voltage issue or would they both go bad at the same time?