Ok, I'm new to this forum because the last forum I was in didn't help, and I alsoforgot what my login was. But I am reallypissed, and even if there is another thread that someone can point me to, I'd still really appreciate it.

Anyway, history:I own a '97 dak 3.9l 4x4 ex cab. When I boughtit (feb '07) there was a fuel pump issue that caused it to turn over for about 3+ seconds before it would fire. We gota new pump and supposedly injectors put inat a dealership. The motor always seemed to have a bit of a surging feeling when you would slowly let off the brake, soI asked the dealer about it as well. They ran diagnostics and said that there may be a cracked head, because there was a cylinder 3 misfire code, and the compression test showed some air leaked out? (whatI was told). So they said "see what happens"

Eventually there were some major problems (nov '07) the surging was still around, but this time the engine light came on and said both cam position sensor, and crank position sensor were...broke. I guess. Some other guy did the work, and the truck ran for 1 M*THERF***ING WEEKand died again. (did he jip me? can't you only purchase a new distributorto get the cam sensor? if so, why did my distributor look the same..?)

The problem was undiagnosable, and bounced around from garage to garage until my father and I said f*ck it, and went to put a new motor in it (May '08). The head was found not to be cracked, but the number 3 cylinder still wouldmisfire now and then. The exhaust vlave lobe on the cam was pitted, but sooo little, that it baffled me as to why that would cause the problem. I wasalso told my computer kept "resetting itself" and it wouldn't run properly.

Soa new motor was put in from a salvage yard, with around 80k(...supposedly). I was told it was taken for a test drive, and went well. I picked it up, drove it home, and did my errands for therest of theday stopping from house to house, parking space to food joint, letting people see that "little red" had returned.

Saturday May 24th, 2008, the day after I got my truck back...she didn't "run". [sm=headbang.gif](Did I get hosed on this engine deal? did he take from my old engine and reuse?)

To best describe how the truck "runs" is like 1 cylinder isn't even working. sometimes it will run for a few seconds, but you will need to hit the gas. Even then, It is undrivable. the rpms go fromaround 800 to 1,500 and bounce around like a retarded tempo meter. if you hit the gas, it just increases the rpms (and loud exhaust noises) but still bounces around. If you don't give it gas, it stalls, and sometimes wont start back up.

If the salvage yard really did put in a new motor, that leads me to believe I have a fuel, or electrical problem...that makes sense right? I tried plugging in another computer but it didn't help (maybe bad harness?) so what else is wrong with my baby?

I'm lost. My truck and I need serious help, but lets get to my truck first. Please anything you can think of, or if you have questions let me know. I'm sorry this post is huge, but I figure the more information out there the easier it will be to diagnose. Thanks, a very pissed dak owner.

 

Well, on engine one, if cylinder 3 was not holding compression (that has nothing to do with electrical or fuel)that is where you should have concentrated your efforts. That usually means bad valves/seats/springs or piston rings.

With a new engine and new issue you are really back to square one with a lot more variables as everything was disconnected

I assume you get a misfire code on cylinder one? You can either pay to have it diagnosed again, or start with the backyard stuff.... Plugs (gapped correctly), wires as well and inspect the FI and wires.

I think you have more issues than cylinder one though. One cylinder not firing would not prevent it fromrunning. It will run worth crap, and you really should not run one cylinder down, but it will run. So with that I would add try to determine if it is a fuel delivery or possible spark issue to narrow this down a bit. If it is not running at all pull the fuel line off and turn on the key, does gas come out the line? With an electric fuel pump just turning the key will move the gas. Just make sure to have a container to catch it.

 

Alright,I'll try the little stuff out myself, and scan the computer (I actually didn'tget amisfore code on my #1 cyl yet..).I really don't want to throw money at diagnostics again, as that gets real expensive real quick.

As for my first engines 3rd cylinder not holding compression, I think that was bull, and them trying to get more money out of me. Before I got the "new motor" that head was taken off, and there was nothing noticeably different between any of the 6 valves, or the way they were seating. (they said that the air was comming out of the tail pipe).

So lets say the people that put in the new motor kept my old intake manifold. (because I think they did) Do you think there is anything wrong with the parts on that could somehow be loose causing it to act up now and then?

And remember, the truck ran better than ever on friday, and today it's suddenly useless.

Thank you

 

torch,
where are you located, i have a real obd2 diagnostic scanner you are more than welcome to use.

 

I am located in Southwick, MA.

But, some semi good news today... Today around noon, I thought I'd try to start my truck up again. Last night I had unplugged what everwire is going into my number 3 cylinder. I still haven't gotten it scanned, so I didn't even know if it was the problem tho. I started it with the injector wire thing unplugged, and it seemed to run a little different.

I plugged it back in, and tried the cylinder 1 plug as well, (because for some reason it worked before I got a new engine). Well it was running much better than it was yesterday, and was slowly getting better as she warmed up.I asked my dad to pick up a can of seafoam while he was out and tried giving it a little of that, why not right?

well, I guess that worked...for now. the truck is running nice today, and I got to go out for a bit, but what if this happens again? I can not trust my truck, and that is not a good feeling.

 

Ok, heres an update:

The truck did it's thing again this morning, so I used the rest of the seafoam (pretty fun stuff haha), but it didn't seem to help.

Only as the truck warmed up again it would slowly stop popping and stuff less. Once it was driveable, I went to an AdvanceAuto, and had it scanned.

I got P1391-which was "loss of crank or cam" and I had those replaced before the new motor like I said, so is it possible something (not replaced) came loose?
p0201 and p0203- "injector control"which I'm hoping are there just because I unplugged them while the motor was running.
And p0351-which says "ignition coil #1 ckt"...and I guess I'm lost on that one.

Anyone?

 

I had VERY similar symptoms and it was my crank sensor. It would back fire and not fire the coil at the right time. Hook at timing light to the coil to dist cap. See if it goes on at the right times. Mine would fire randomly, no misfire codes because as it knew it was working properly. And yes, your engine shouldn't even run if the crank or cam is off. I think maybe it was installed at a slant or something weird. I changed mine up and Vroom she ran like a champ. Also check your wires, maybe double and triple. This happened to me when installing my 5.9 in.

Chris

 

Ok, thanks Varsis, I don't understand how something like that can just "warm up" into running smoothly, but I'll let you know.

Also,a question to you, how is your engine swap going? When I was looking for a new engine, I wanted to swap out for at least the 5.2 (but the new 3.7 or 4.7 would have made me happy), but the guy I have do most of my work said that he talked to his transmission buddy, and he said that I would have to do a whole bottom end swap as well.

Don'tthe trucks with a5.2 still used the same 4sp Auto transmission, and would that extra 50hp really rip up the torque converter and back...?

Thanks all.

 

The 5.2L came with the 46RE, which is stronger than the 42RE. But, there are guys that swapped their 3.9L's for 5.2L or 5.9L and retained their 42RE, and are running without problems. Now, if you beat on the truck all the time (burn outs, red-line all the time, etc etc) the life of the transmission will certainly be lowered, but it's been done.

As far as the 3.7L or 4.7L, that would require a differant transmission, since the automatics behind those are fully electronic, and have their own computers.

 

oh, hmm I'll try to remember that, and good to know. Thanks dodgerules86 haha.

As for another update...: I talked to the guy that did the cam and crank sensors back in the day, and he said ifI get it running, bring it in and he will look at it.

It, no joke, went like this: Walk outside, put key in ignition, starts and runs stupidly rough, pop the hood, put my hand on the distributor, and wiggled it around... and it ran nice.
NowI don't know if that had anything to do with it, but I do know it makes mea little mad that no one before me thought anything about timing.