12 valve won't idle
 

I'm new to this and put my question in the wrong place to start with so I hope I'm in the right place now. I have a 1996 Dodge Cummins with ATS auto trans, ATS aurora 3000 turbo, Pensacola Diesel stage 1 injectors, TST #5 plate and timing at 20 deg. I have idle issues. problem started about 5 months ago and is getting worse. It won't idle when the engine is warmed up. It seems to be worse on warm days. Otherwise it runs great. I have changed the overflow valve and the speed sensor on the transmission with no change in the idle problem. Any suggestions?

does it smoke white? does it miss when you slowly rev it up in neutral?

won't idle
 

No white smoke or at least very little. It accelerates and runs good. I've tried raising the idle, but that only helps temporarily and now it idles over 1000 rpm when the engine is cold or outside temp is cool. But starts dying again when things warm up.

sounds like the pump might need to come off.

won't idle
 

That could be the problem, but I don't want to spend that much if I'm not sure. It does idle ok in park or neutral, it only has the problem when its in gear. Could it be a transmission problem? It doesn't have any problems pulling a load and runs good when moving.

how low is the stall in the converter? a very low stall can drag one down. also inpropperly installed govoner springs in the pump can cause it to die in gear.

won't idle
 

The torque converter is an ATS its been in the truck for 6 years and 110,000 miles. I'll have to check with ATS foe specs. I've never changed governor springs there stock.

Could be trying to take off in second gear, causing a lower idle ... Possibly ... Maybe lock up solenoid is partially sticking ??

VB issue, when was the last time the trans was serviced ??

fuel filter, fuel pressure, any of these things ot a combination of these can and will cause issues ...

12 valve won't idle
 

All good suggestions and I'll pursue them. The transmission is due for an fluid change and band adjustment. It runs good other than the idle. I stayed with a 14 RAM 3500 diesel today, we both had 30 foot travel trailers going over some of the passes in Colo. No problem staying with Him.

huh... changed your fuel filter recently as well ?

Do you have a tork tek OFV ?

I recently did mine .. WOW !!!! 1.2 Mpg in my truck and nice throttle responce now too ..

wont idle
 

I change the fuel filter pretty regularly. I don't know what tork tek OFV is.

its a Restriction valvethat allows the owner to adjust the Fuel pressure on the fly .. you will need a fue pressure guage , from tork tek its set @ 30-32 psi which is real good .. and it will stay real good as long as your Lift pump is not getting weak ...

Larryb - LarryB's Dodge Diesel, 94-98, Fuel Pressure Adjustment Kit

This kit is perfect for a guy who wants to do it him self, and dosent require any "Special Tools "...

Keep us posted ..

won't idle
 

Ok I should have known what that was. I have changed the overflow valve, just last week.
I put in an adjustable valve its set at the pressures you mention, I got it from Cummins Performance Parts, but don't know the brand. I didn't see any difference.

My 95 auto had a similar issue, it was the TPS that was the cause. Check the wires make sure nothing is warn or damaged. There should be a write up somewhere to test it. Worse case it is not terribly expensive to replace before getting into more money. There is another write up around about replacing it with a home built set up, but I swapped the proper TPS back in and problem solved.

?? Wrong thread I think ... Lol:humm:

Nope, my 95 idled and died often after warm up, also felt like a wet noodle leaving the line then would wake up. I replaced the TPS on it and it was all good. I initially thought I had fuel issues and was all over it until I read a post another guy had on the issue.

Odd, Tps and fuel on a 12V are not related to one another ... maybe it was the signal to Trans from tps ???

Mechanical engine dosent need input from the TPS ... maybe it was doing the 2nd gear take off instead of 1st gear ... which would explain the issue ...

won't idle
 

I'll give that a try. thanks

Do please keep us posted on this ... I am curious what you find out:humm:

won't idle
 

Over the weekend I flushed the transmission, changed the filter and cleaned the oil pan (It was actually pretty clean) adjusted the bands. No affect, it still won't idle when warmed up. I changed the TPS and checked all the wiring, no affect. I cleaned the fuel heater pre filter and changed the fuel filter. No change. It still won't Idle in gear when its warmed up. Its fine in park or neutral. Seems to have plenty of power except when initially starting out, it takes a little time to spool then it has plenty of power.

Won't Idle
 

Found the problem. About a year ago I installed a set of Pensacola Injection stage 1 injectors. I removed them and reinstalled the stock injectors. The idle problem is gone.
Thanks for all your input and advise.