94 Ram Multiple Issues

[sandman96]

Hi all. I've got a 94 Ram 5.2 318 automatic with approx 207K miles on it. Several years ago I started getting check engine lights when the temp just started to go up on the temp gauge. At this same time I had problems with the truck wanting to die when at idle. Was told by a friend that is a mechanic at a Dodge dealership that it was a bad EGR sensor and I could just unplug the vacuum line. This trips the check engine light but fixed the dying issue. Now the truck is having problems staying running when at idle, also if I suddenly take my foot off the gas and brake the RPM takes such a sudden drop that the truck dies. I've also noticed the truck feels like it's bogged down at times when trying to accelerate and surges when braking. Just over the past two days the truck does not want to shift from 3rd to 4th gear when cold. I was riding the brake and gas pedal on my way home today, to keep the truck from dying, and after I parked noticed the brake lights where on. Lifting up on the brake pedal with my foot turned them off. Any idea where to start?

[jamesslcx]

Sandman96, what are the codes? I would reconnect that vacuum line and fix that bad egr or egr solenoid. Sound like you have a brake switch problem as well. Really need those codes to help diagnose, running problem could be a lot of things such as tps sensor etc.

[sandman96]

I'll have to check the codes again to be sure what they are, there's at least two of them maybe three. What negative effects can not having the EGR hooked up have? Been told by several mechanics that it's no big deal to not have it. Another mechanic I talked to today about this said something about a cold circuit sensor or something like that.

[sandman96]

I checked the codes, even made a video of it lol. Codes displayed in order are: 12, 32, 17, 32, 55. By my memory the battery has not been disconnected within the last 50 restarts (code 12). The temp gauge never gets up to the middle position during colder winter days. And during the summer it goes slightly past the middle position. I'll have to look at the temp markings to see what exactly it gets to (code 17). Code 32 is the EGR but don't know why it's in there twice.

[sandman96]

So this morning it was about 35 degree's and the drive to work went without a hitch. Temp went to a steady 180 (middle of the gauge is 200). Now when I drove home from work it was about 60 degrees, and it started having the dying problem again. Temp took an abnormal amount of time to go up. And it just barely got past the 180 mark on the gauge. Considering the outside temp being around 60 it seems unusual for it to take so long to warm up and even then not get up to the 200 mark. Another thing I noticed, it didn't start trying to die until the temp got above 180.

[jamesslcx]

Sandman, sounds to me like it is running a little too cool, might be thermostat time. Make sure your battery is good and all your connections are clean and tight. Egr system failed to respond to commands(code32), code 17 is engine running too cool, code55 means the end and also code 32 means Malfunction indicator lamp inop, so mostly thermostat problems and probably a battery or battery connection problem.

[sandman96]

Thanks for the help jamesslcx. What does malfunction indicator lamp inop mean? Also if I get a new thermostat and the truck starts running at a normal temp, which would be a higher temp than it is currently, would this not just make the dying at idle problem worse? The only time the truck wants to die is when the temp gets above 180. At or below 180 the truck runs great except for not wanting to shift into 4th when cold.

[jamesslcx]

Sandman I guess It means you check engine light is supposedly not working.? Your truck computer uses engine temperature to adjust the fuel mixture, timing etc so it can run right. I think your computer is confused because of the medium temperature of your engine and cycles between open loop and closed loop. In other words it is having a hard time adjusting your trucks fuel and timing because of the temp. I didn't word that well but I hope you get the point.

[sandman96]

Cleaning the throttle body with some carb cleaner has fixed the dying problem. Will be replacing the thermostat this weekend and have a new EGR valve on order that will hopefully be here Friday. On the downside my brake lights have been staying on today, even when parked and the truck is shut off. How hard is replacing a brake switch and where is it located?

[jamesslcx]

Good work Sandman, the brake light switch is usually located on the shaft that holds the brake pedal.

[sandman96]

Been a while since I updated this. Got all the things from above done (thermostat, EGR valve, and cleaning the throttle body) For the first time in about 7 years my check engine light is not on!

But now a new problem has came up and I fear it will be much more expensive. The transmission is having shifting problems from 3rd to 4th when truck is cold. This used to happen occasionally and letting off the gas would let it shift but not anymore and it happens every time the truck is cold. Once it does get through all four gears it's fine after that and shifts normal. Nothing has ever been done to the transmission, no fluid changes or flush. One person I've talked to says don't touch the fluid because it's high mileage and never been changed. He said it's probably rebuild time and changing or flushing would cause bigger problems. Any advice?