Hello all,

I am new here, so hope this is in the right spot. I have this problem no one can figure out and neither can I.

I have been searching trying all kinds of things to no end.

1997 5.2L Dodge Dakota SLT 4x4

Problem:

Hard to Explain but here goes. When you place the truck in 'Gear' (Reverse, Drive, What ever) you can slightly feel it in the truck it self while pressing the break, but really when you let off the break and are very slow (not giving it gas from a stop) or slowing down almost to a stop.

I would consider it a loping or shuttering.. like there is an engine miss.. kinda like how a high performance engine lops, but in this case the hole truck.. a jerking feeling like it wants to go but doesnt want to go..

Drives fine, shifts fine, has plenty of power.. sometimes I feel a hesitation. Like a miss.

Here is what I have done so far:

1. Plugs, Cap, Rotor
2. Wires
3. Tested the Comp ratio (all testing fine by shop)
4. Injector Cleaner
5. Replaced the PCV valve (not sure if right name but the check valve on valve cover)
(But I still hear it engaging constantly.. I can pull it out and it does not affect the main problem, just a side note)
6. NO oil burning, smoking or anything
7. Shop put new tires on it.. LOL
8. Break job
9. Not sure what else they did
10. It was at the shop for a week no fix

One day sitting in line for 20 mins in drive, inline at Taco bell, check engine light came on

Code: #7 Misfire

After driving it around for 2 days it went off.. Code still present but I cant get it to come back on no matter what i try..

I am at witts in, going to check my routing of cables and I've read alot about the IAC, TPS, ECT and some other things..

I'm going to try the IAC/ICE what ever it is, the one that controls air flow while its got its main intakes closed?

Again it seams the problem on persists when ever its almost at a stop.. but runs fine.. it only seems to do it when not pressing the gas peddle at very almost a dead stop or rolling from a dead stop or to a dead stop.

What am I missing, and I barking up the right tree with the IAC.. with the number 7 misfire?

Only thing I have not done is clean injectors.. any input would be greatly appreciative.

 

Also, I swear I hear a miss sound in the engine.. and even in park.. you can watch the antana go back and forth as if it was going down the road..

Engine is very smoth as far as movement to gear out of gear, and such, so do not think its mounts.

Defently feels sounds like a miss of some kind.. like it wants to go but then it doesnt want to go.. Thanks

 

Bump.. TTTT anyone? Thank you in advance

 

To me it sounds like a crankshaft position sensor, but with these trucks you never know. One sensor could be bad causing a completely different problem that you might not think of.

 

Thank you for your reply, I was actually thinking about that sensor, I was told by a few people it should be replaced every 75,000 miles..

This sensor, would it throw a code or would just make it run bad?

 

any codes now? swap the coil and see if if you still get a misfire

 

I've replaced the Plugs, Wires, redone routing to ensure 5 & 7 were more than 1 inch apart, same for 8 & 4 and main wire from Coil to Dist. as one document stated..

I did notice the nipple on the coil was a bit corroded (Not rust more like varished) I took sand paper to it to make it nice and shiny..

I have not replaced the coil though as typically a misfire from coil would be pretty constant moving from cylinder to cylinder correct?

Anyhow, I actually only got the Misfire once.. and after a day of driving it went out.. and no codes since.

The shop even supposedly tested the compression and passed, as well as voltage rate coming from coil. So they said both were fine.

 

it may throw a code intermittently. it may make the truck not start or run properly. that part really is a ghost in the machine. if you live near the coast or somewhere where they salt the roads, take a look at the crankshaft position sensor. its exposed metal and once corroded, it slowly goes and causes weird problems.

 

Yeah truck starts and runs fine.. basically, it does feel like there is a miss, kinda like a rough idle.. but the main problem I have is best way to describe is this: in gear, stopped, take your foot off the break and then its like a jerking feeling.. like it wants to go but hesitates.. give it gas to go and runs fine, beautiful. I swear like it when you really get on it sometimes* kinda feels like a hesitation.. but mostly you can stomp the gas and it gets up and moves..

Mainly though like I said.. taking your foot off the break, no gas.. creeping.. or once you get down low enough coming to a stop sigh or something with out your foot on the gas once you get slow enough i'd say 1mph~5ish it does it.. I do not think its in the tranny as it would still do it with your foot on the break.

I've been troubleshooting an ignition fuel problem but I'm not sure anymore wth this is..

 

Ok.. so here is the update..

1. Replaced Coil- No change (does feel a bit more 'pepy') Coil reads 1 Ohm, and food for thought, old coil, that fins was a little rusted and starting to have space between, also read around 1.1~1.3 ohm.

2. Went ahead and changed Rotor, Cap, just because I do not trust the shop that did the work.. and I really could not tell if they were new or not..

So all in all, still in the same boat.

I am thinking about taking it down to wally-world, they have for about 35 a high pressure injector cleaning, they hook a machine up to the fuel rail and high pressure cleans it, then puts pro-grade (so the say) cleaner in the tank.

All sensors checking out, no codes, vacuum seems fine, I can not really image what it could be other than something mechanical.