Engine replacement problems

I have the 1994 GC w/ 5.2 L. I just replaced the 160k mile engine with a j/y 80k mile engine out of the 1995 JGC. I heard the engine run before the j/y pulled it, it was fine. Now that I have the engine in my truck it is having a few problems. I am having driving problems. The thing starts and idles fine but when I drive it I leave a trail of black/brown smoke and carbon residue behind me and it stumbles until it dies. It seems like too much fuel. I have changed the O rings in the injectors. I think that I have either put the timing chain on a tooth off (which if I had, would it run?)or I have injector plugs backwards, TPS problems or coolant temperature sensor problems. Has anyone else had this problem? If so what was the outcome?

It is possible the timing chain is off a hair. To check it set the #1 cylinder at TDC on the compression stroke, then remove the distributor cap, the rotor button should be pointing at the #1 terminal on the cap.

Double check the injector wiring, Each injector has 1 wire that is the same on each injector (Dark Green/Orange), then the other wire is a different color for each wire.

#1 Cylinder - White/Dark Blue
#2 Cylinder - Tan
#3 Cylinder - Yellow/White
#4 Cylinder - Light Blue/Brown
#5 Cylinder - Grey
#6 Cylinder - Brown/Yellow
#7 Cylinder - Dark Blue/White
#8 Cylinder - Dark Blue/Yellow

Ok, I took the front end apart and recehcked my timing chain. Needless to say that was expensive. The timing marks were right in line. I checked the fuel injector plugs for them being out of order, they were fine. I took apart my throttle body and cleaned it rotten and the d""" thing still runs like crap, & still blowing out black smoke (too much fuel). There are no codes showing. I tried to get the TPS off and replace it but the thing would not come off. One of the screws are stuck. I think I'm going to be replacing the throttle body. I checked at the parts store, the injectors between the 94 and 95 are the same (because the eng. I just put in was a 95 into my 94). I am going to do a complete sensor replacement on payday and see if that will do the trick.

I just went out and lined up the TDC on the harmonic balancer with 0 on the timing cover and the rotor was 180 out so I pulled the dist. and turned the shaft and the thing just backfired repeatedly. I noticed that when I put on the timing chain that the rotor was not on the 1 mark when I lined up the marks. The thing is is that the engine ran fine before it was pulled and when I replaced the timing chain all I did was remove the timing set, put the timing gears in line with the marks, took off the top gear and put the chain around it and set the chain on the two gears and lined the marks up with a ruler. I noticed then that the rotor was facing 180 out of 1 so it must be the V6 mark is the power stroke? and It puzzled me then and it puzzles me now. So what it means is that its at the top to go down to make the compression stroke?

Is it possible that the crank sensor was damaged when you put the engine in?

I just went out and lined up the TDC on the harmonic balancer with 0 on the timing cover and the rotor was 180 out so I pulled the dist. and turned the shaft and the thing just backfired repeatedly. I noticed that when I put on the timing chain that the rotor was not on the 1 mark when I lined up the marks. The thing is is that the engine ran fine before it was pulled and when I replaced the timing chain all I did was remove the timing set, put the timing gears in line with the marks, took off the top gear and put the chain around it and set the chain on the two gears and lined the marks up with a ruler. I noticed then that the rotor was facing 180 out of 1 so it must be the V6 mark is the power stroke? and It puzzled me then and it puzzles me now. So what it means is that its at the top to go down to make the compression stroke?


Well before you reset the timing when you thought it was 180 off, it prolly wasn't 180 off, you prolly didn't have the the Crank set at TDC "On the compression stroke" it was prolly TDC on the exhaust stroke.


And when you pulled the gears and chain off the cam and the crank shafts, did you remove all the spark plugs before doing so. The reason I ask is the when you pulled the chain/gears if the plugs were still in the head then you would still have compression in some of the cylinders so that compression would cause the crank to spin out of alignment, then that would cause you timing to be off a hair.

The reason you get the backfiring now is because it is out of time, you will need to spin the distributor back 180 degrees.

I did, I put it back to the original position. Thank God it's not like the older Fords where the thing can catch onto the oil pump a million ways. A simple turn of the shaft and you're back where you were.
Yeah, when I put the timing chain on there were no spark plugs, makes for an easier turn of the crank w/o them in. I think I've just about had my fill of the thing and am just going to sell it. Maybe someone else will have the patience for it.

Is it possible that the crank sensor was damaged when you put the engine in?

That's a good question, I was thinking of replacing it with every other sensor until it ran right.

Let us know.It's real easy to smash the crank sensor against the trans when you put the motor in.You don't have a lot of room to line it up .Also,I have seen the wire harness get caught between the trans and motor.That usually causes a no start,but a cracked sensor usually runs like crap.Good luck

Ok, I replaced the CPS, cap, rotor, plugs and wires and still running bad. It will idle fine for awhile then it blows out the black smoke and dies. It's dumping in a bunch of gas. The computer is telling it to flood it with gas; why? Maybe next should go for the fuel pressure regulator?

Ok, I replaced the CPS, cap, rotor, plugs and wires and still running bad. It will idle fine for awhile then it blows out the black smoke and dies. It's dumping in a bunch of gas. The computer is telling it to flood it with gas; why? Maybe next should go for the fuel pressure regulator?


Test the TPS (Throttle Position Sensor) with a voltmeter, backprobe the center wire of the TPS with the positive lead of the voltmeter, and ground the negative lead to the negative battery terminal, then turn the key to the ON position, the meter should read between .2 - .9 volts at idle.

If it is dummping a bunch of gas, it is prolly because the TPS is telling the computer that your throttle is at half throttle or so, when really it's at idle. if so, your voltage reading shoul dbe alot higher then.9 volts (but a good TPS the reading should be between .2 volts - .9 volts).

do you have access to a scanner?

do you have access to a scanner?

yes

I did, I put it back to the original position. Thank God it's not like the older Fords where the thing can catch onto the oil pump a million ways. A simple turn of the shaft and you're back where you were.
Yeah, when I put the timing chain on there were no spark plugs, makes for an easier turn of the crank w/o them in. I think I've just about had my fill of the thing and am just going to sell it. Maybe someone else will have the patience for it.

I agree older ford rotors are a certifiable nightmare.
also if your engine has a knock sensor that may be the culprate. combine a bad sensor with erratic timing and the computer will dump tons of fuel in it. i am just not sure if that engine has it

Your only suppose to have 1 O2 Sensor, 96 and later vehicle have 2 O2 Sensor, federal emissiona, V8 models with california emissions has 4 O2 Sensors.

Really, the guy at the auto parts place was adiment that there was two. I'll check and see if that's in my manual and show him. I looked this morning and could not find any more wires. I knew the guy was mistaking.

Damn dude, you went about this all wrong...sounds like you had a map sensor problem. The MAP is your engine load sensor, this is your main fuel metering input to the PCM. A broken vacuum hose to the Map will do the same thing.

Damn dude, you went about this all wrong...sounds like you had a map sensor problem. The MAP is your engine load sensor, this is your main fuel metering input to the PCM. A broken vacuum hose to the Map will do the same thing.

Nope, didn't work. Still idles rough and still blowing blk smoke. The only thing left is Idle control and Elec control module. Next payday!! I spent $300. this payday on it all ready.

Slow down man, stop throwing parts at this thing! If you're problem is rough idle and black smoke it's definitely an over fueling problem. Do you have access to a scan tool? If you could list off your values on your datastream with it running we can help you nail down your problem. Does it do this when it's first started? How soon does it start to run bad?

Slow down man, stop throwing parts at this thing! If you're problem is rough idle and black smoke it's definitely an over fueling problem. Do you have access to a scan tool? If you could list off your values on your datastream with it running we can help you nail down your problem. Does it do this when it's first started? How soon does it start to run bad?

Yeah, Im done throwing parts at it. I finally broke down, swallowed my pride and called Chrysler for an appointment. I have spent more in parts than I think Chrysler would have charged me to diagnose and fix it.
When it starts it runs rough. It blows black smoke. It's not as bad as what it was since the new parts are on but the smoke is still there none the less. The idle becomes fairly smooth but the engine just sets in there and rocks back and forth on its mounts. I let it warm up and when I put it in drive or Rev. it sputters and the RPMs drop to near 0, it shutters and acts stupid and it will not move. So idling is fine but driving and reverse wont work. The tranny is brand new, 200 miles on it. The engine I bought had only 80k miles. I have replaced almost every sensor so I don't think those ar the problems.

Are you sure you have the firing order right?

Are you sure you have the firing order right?

Yeah, I went out and rechecked them, they're all in order. I took the front end of the engine apart and checked the timing chain a few weeks ago and it was fine. Maybe the coil? Maybe the coil isnt throwing enough juice to the plugs to burn the fuel properly and therefore it's reading too rich? I think I'll throw a coil on there and see what happens.

Ok, I took an old spark plug and unkooked #1 plug wire and plugged in the old plug and checked the spark. #1 was a really dull yellow spark as were 2-8 with a new spark plug. Maybe coil or PCM?

I had the coil checked, it was within perameters. What else controls spark strength? What about the Cam Positioning Sensor and the ECM? I'll do the wires tomorrow and see what happens.

Maybe I missed it but, when you installed your new engine, did you put only the motor in (with head of course) and then put on the manifold and FI from the old engine?
If you used the Intake/TB and FI from the newer engine, that may be your problem. You should keep anything that has to do with ignition and FI from the original engine, as the sensors from another year may not be compatible.

I had a problem similar to yours on a transplant that I did. I told the mechanic to put my old manifold (TBI) in the new engine, he did not think that was nessesary, the engine would idle but had no power, I had to change it myself b/c he did not believe me. After changing the intake (with the TBI on it) it ran the way it was supposed to.
It turns out that my car was CA emission and the engine was FED.

I didn't change the manifold no. The throttle body yes. I guess I should go and see if the j/y still has my old engine. Before I took the engine back I did check to make sure everything was exactly the same. The only difference I could see was that the fuel rail was different. I checked with the local parts store to make sure the coil, dist., injectors etc was all the same parts numbers. As I replaced the sensors I checked to make sure the parts numbers inter mixed between the 94-95 5.2 and each one did. I'm kind of leaning towards the PCM right now. My alarm quit working, which is nice because I got tired of that noise. My spark is very very weak. I think I may have done something to the computer when I did all of this.

douge,

did you change the fuel rail... the 95 and later 5.2l don't have the fuel pressure regulator on the rail, which would mean you wouldn't have pressure regulator at all...... = too much fuel..
l

I did change the fuel rail yes but the injectors were the exact same part # as the 94 so I left them. I also changed the fuel pressure regulator.