I'm stumped

[moparzrule]

My 90' 2.5 TBI dakota runs like crap intermittently and it's seems to do it more often when it's cold outside. It misses, stalls, very low on power. WOT does not clear it up, so I've eliminated the O2 sensor. Here's a list of things new in the last 6 thousand miles-
fuel pump
cap/rotor
plug wires
coil
plugs-RN12Yc's

It just started doing this last week. About a week after I chopped off the exhuast right after the cat and put a cherry bomb on with a turndown. So the stock cat is there giving plenty of backpressure.
I ran a bottle of injector cleaner through it, no dice. Check all connections and vacuum lines, nothing. The kicker is sometimes it runs fine, just great. This lead my to think the distributor thingy in there was loose, wasn't. Then I thought it was the coil, replaced it, no difference. The only thing left is the HEP, but wouldn't it be throwing a code for that? Why intermittant? Mostly in cold weather??? Only code I get is 55. Nothing, I'm stumped.

[overlordsshadow]

Intermitant are the worst. Could be grounding, heat or moisture?

[moparzrule]

Tell me about it. I'll check the grounds, what do you mean by heat or moisture?
So far it's been acting crappy on the way to work for the past 4 days. Coming home from work, runs like a champ. I'm like WTF!!!

[moparzrule]

I was thinking about resetting the ECU, couldn't hurt right?

[overlordsshadow]

Well I'm thinking moisture in the dist mabye. But I remember that cold wether made my acting up/ dying coil be a ----- to me. I would work weddings until like 2am out of town at a rural wedding place and it was damp and cold and for some reason that gave me coil problems. Does ures have the solid coil on the tstat house or is it still running the liquid on the pass side?

[moparzrule]

It's the round oil-filled coil. But I tried replacing the coil yesterday, didn't make any difference.
This morning when I got to work I popped the hood to check the distributor, no moisture in there and everything seemed fine.
I'm leaning toward the HEP, but I've already put out $30 for a new coil and it wasn't the problem.

[overlordsshadow]

Then jy it and grab a new hep? I know you said your wires and such are fairly new but did you check over the plugs and wires, mainly the part that is in the dist?

[turbovanman²]

HEP wont' give you low power, it will either run or not.

How's the fuel filter-did you change it when you did the fuel pump? is there crap in the tank, had many a intermittant problem caused by that.

Check all grounds and maybe add a few. If theres no codes, fuel pressure and volume are good, good grounds etc, you could have a bad ECU, has happened to me before.

Are the cat internals loose?

For the price of the coolant temp sensor, try that, they've been known to glitch out and not set a code, same with the intake temp. The coolant temp should be the same as a TM.

[moparzrule]

Yeah checked the wires in the cap.

Simon, yes changed the filter, my bad should have mentioned that. The tank came completely off and got a cleaning before new install.
CAT was intact and seemed in good shape. Do TBI have a intake temp sensor? Coolant temp sensor kinda makes sense, that could be it. Thanks for the insight simon.

[turbovanman²]

Yeah checked the wires in the cap.

Simon, yes changed the filter, my bad should have mentioned that. The tank came completely off and got a cleaning before new install.
CAT was intact and seemed in good shape. Do TBI have a intake temp sensor? Coolant temp sensor kinda makes sense, that could be it. Thanks for the insight simon.

They have an air temp sensor at the throttle body, they use it for hot restarts but if its acting up, you never know.

[moparzrule]

It always fires right back up if it stalls. Does that make a difference?

[turbovanman²]

It always fires right back up if it stalls. Does that make a difference?

Not really.

Next time it does it, measure the injector, it could be on its way out.

[Vigo]

didnt read the whole thread but..... bad connection at the map sensor.

[moparzrule]

I'll check that out VIGO, thank you.

Simon, how do I measure the injector??? Thanks

[22mopar]

I'll check that out VIGO, thank you.

Simon, how do I measure the injector??? Thanks

here's one no-one mentioned. throw a coil at it. the e-laminated coils are known for these symptoms. I had the same problem because of a faulty coil.

[overlordsshadow]

Coil was replaced since start of thread.

[moparzrule]

LOL, thanks overlordshadow.

Checked the MAP connection and it's vacuum line, all good.

It's been slightly better recently, I think the injector cleaner worked some. So I'm thinking the injector is the issue since I haven't done anything else yet.

[jre97]

When you replaced the fuel pump did you get it plugged all the way back in? If it's the small style plug you might check to make sure the pins in the pump side of the connector didn't get pushed in too far. I had a similiar problem and it drove me nuts. Sometimes my 91 lebaron would run fine and then it would act like it was running out of gas. It was the connection at the pump.

[turbovanman²]

When it acts up, you disconnect the injector and measure the resistance.


Vigo jogged my memory, older TBI's had big time issues with bad MAPS. Maybe try a known good one, I had a customers car do the same thing so I guessed at it, I had him carry the good one, when his car stalled and lost power, He plugged it in and fixed.

[moparzrule]

I seriously doubt it's the connection at the fuel pump, there was a distict ''click'' when the connector went on. And all the wires were in excellent condition, I was really shocked because when I put the 255 pump in my daytona I had to re-do everything because it was nasty looking.
Simon, I thought a 90' was a newer TBI? Regardless, I think I'll pick up another MAP sensor when I go to the junkyard. I'm gonna be on vacation for the next week, starting tomorrow so it won't be for awhile until I get to the yard. Although I'll look up what a new one costs and if it's under $20 it's worth a shot, but I doubt it's under 20.
Thanks

[JDAWG]

Matt an new one from Chrysler is $100. You need to look for 89up. Here are some #'s 5227351, 4638256, 5014762aa

[turbokid]

running like crap means??? Is it surging?? My glhs would run like a champ then all the sudden lose power and surge and finally die. then would start right back up. Found out it was the fuel pump.

[Vigo]

i forgot about the time i had an issue like this, and it did turn out to be the injector. it was getting stuck open or leaking or both, but it eventually got so bad to drive, i turned around and went back home one morning, turned on the key and was checking stuff on the scanner, and by the time i smelled fuel, gas was pouring out of the airbox!!!!1

let me just tell you what i felt at that moment

OMGWTF!@~@#!@#@!@#!~!!!!!!!!!!!!!!!!!!!11111!!!!!! !!!!!!!!!!!!!!!


yeh i dumped about a gallon of fuel into the motor through the leaking injector in all the time i had the key on. luckily i figured this out before i tried to crank it.

so i drained out the oil/gas, about 2 drain pans full : o

went across town to my parts pile at my parents, grabbed an injector, threw it on and had it running and got to school in time for my second class.


and as i recall it was very intermittent at first but got worse and worse..

so might wanna check and make sure you arent dumping fuel when its running bad or that its leaking with the car off.

[moparzrule]

and as i recall it was very intermittent at first but got worse and worse..
.


This thread is 5 months old, but yeah this was the issue. It did get to the point that is was bucking so hard with barely any throttle. Had a spare throttle body, just replaced the whole thing and the problem was gone. Sorry I never updated this thread but I didn't want to bring it back from the dead.

[John B]

This thread is 5 months old, but yeah this was the issue. It did get to the point that is was bucking so hard with barely any throttle. Had a spare throttle body, just replaced the whole thing and the problem was gone. Sorry I never updated this thread but I didn't want to bring it back from the dead.

Sorry to resurrect this old thread, but I want to know what part of the throttle body was bad? I am having real problems with my car and it has a different throttle body from the original.

[Vigo]

i think it was the injector.

[turbovanman²]

Sorry to resurrect this old thread, but I want to know what part of the throttle body was bad? I am having real problems with my car and it has a different throttle body from the original.

I would lay money on the injector being bad.