2002 Runs rough and lacks power

[bcstoy]

Hi I am new to this list and in desperation I decided to post my problem.
A friend bought this truck with a bad motor. I replaced the motor after that the truck ran decent for 1 day and since then it runs rough and lack acceleration. Here is what I have done:
- replaced coil pack, plugs and wires.
- replaced injectors
- replaced one head gasket (driver side) worried that this side seems prone to problems
- replaced the O2 sensors
- fuel pressure remains 60 PSI
- Compression ranges from 150-175.

I ran the scanner first and the codes that remain after all that work are p0171 (passenger side) and p0175 (rich on the driver side). I may add the codes are not very consistent. At some point I even had misfires on cyl 2, 4,5,6. The p0174 (lean driver side also will show up)

At this point I am ready to conclude the PCM is not commanding the right instructions to the truck to run normal. It has the PATS system incorporated in the PCM so there is no way I could try another computer.

I have smoked the the engine and saw no visible vacuum leaks. The smoke mostly escapes through the air filter housing.
I have played with the idle air valve and nothing either. The only things I have not touched are the MAF and the fuel pump.
I work mostly on Toyota trucks and tried to stay away from Fords but in trying to help this friend I ended up in a constant struggle to get this truck road worthy.

If anyone has had a similar experience I would like to hear it. At this point I am ready to send a used computer to a shop in Florida to reprogram it to the vehicle specs. I am convinced the module is bad. I have seen this problem happen to Nissan trucks, but since I have no experience with Ford I have no idea how common PCM failure is.

Thanks in advance

 

[bcstoy]

for any one interested I just replace the PCM truck had a minor improvement. Thus far codes are: p1152 & p0175. Now both codes are related. I have to keep looking for a solution. If anyone has found one for either code let me know. Otherwise as usual I am on my own. Will never buy a ford.

 

[Brain75]

you replaced the motor... so you put another 3.0L in, same everything, not a flex fuel?
replaced injectors - did you use ford or aftermarket (aftermarket injectors are just plain junk, I'd clean/test the oem and put em back in, literally the aftermarket crapshoot could be all your problems - more than a little likely)

how long did the gas sit while the engine change happened, diagnosis, before starting work? - too old gas would just foul up the injectors.

Injectors, MAF and computer are the biggies for causing both lean and rich to show up especially at the same time... O2 sensors play in there too but I have a hunch they are not it.

Without throwing lots of $$$ doing the parts cannon approach, my first 3 steps would be
Clean the MAF (use MAF cleaner fluid, nothing else - grab a youtube vid on how.)
grab your old injectors, clean and test them - again a youtube video on bench testing, then reinstall the oem injectors.
using a more expensive OBD2 reader I would look at "realtime" while running conditions, not just codes. (Someone confirm this for me, but Forscan and a $30 cable Vgate V-Linker does that.) See what your short term and long term fuel trim is, and how they change with RPMs.

 

[pjtoledo]

random questions, oil pressure? is this a flex fuel Ranger?, does it have the FF module in the fuel line?
try pulling the SPOUT connector/plug. that will limit timing to base 10 degrees.

 

[Brain75]

Intake Air Control Valve ($17 part at rockauto) is another suspect and probably a fairly likely one given you have both lean and rich together.... if it is barely cracked it might not cause issues at high rpm but will at idle, and at low rpm it will cause too rich/lean at high rpm it will cause the opposite.

 

[red Ranger (Sarah)3.0L]

also listen for a knocking i had a similar thing with the misfire codes i had like 1 3 and 4 codes but anyway it was the 3rd cylinder valve spring so possibly a valve spring?

 

[bcstoy]

you replaced the motor... so you put another 3.0L in, same everything, not a flex fuel?
replaced injectors - did you use ford or aftermarket (aftermarket injectors are just plain junk, I'd clean/test the oem and put em back in, literally the aftermarket crapshoot could be all your problems - more than a little likely)

how long did the gas sit while the engine change happened, diagnosis, before starting work? - too old gas would just foul up the injectors.

Injectors, MAF and computer are the biggies for causing both lean and rich to show up especially at the same time... O2 sensors play in there too but I have a hunch they are not it.

Without throwing lots of $$$ doing the parts cannon approach, my first 3 steps would be
Clean the MAF (use MAF cleaner fluid, nothing else - grab a youtube vid on how.)
grab your old injectors, clean and test them - again a youtube video on bench testing, then reinstall the oem injectors.
using a more expensive OBD2 reader I would look at "realtime" while running conditions, not just codes. (Someone confirm this for me, but Forscan and a $30 cable Vgate V-Linker does that.) See what your short term and long term fuel trim is, and how they change with RPMs.

I actually drove the truck from L. Havasu to Phoenix running on 3 cylinders. It ran decent except had no power especially going up hill, vibrating at idle. Thus gas was not an issue. That is why I thought after changing the motor truck should have been running w/o any mayor hick ups. It ran smooth for a day gave it to my friend and asked to bring to me the following week for a follow up. He brought it running bad.

It started throwing all kinds of codes for misfires on 2, 3, 4, 5,6. Besides those lean bank 1 (0171) and rich (0175). Now with the re-flashed pcm it has settled on p1152 and p0175, so far. I did not believe the injectors could be a problem or the coil pack because the truck even on 3 cylinders ran better than now. In desperation and luck finding after market injectors from someone in offer up replaced both coil pack and injectors. I could tell that someone had already worked on the motor and the injectors too.The harness is lousy and some of the locking tabs are broken already.

I may try to download the forscan, what it confused with the instructions posted by someone was the specific elm connector to use. Will try to use my scanner to look at fuel trim (SFT, LFT), obviously given how the truck runs I am sure they are off. The big question is why the truck runs so bad and why has not made any improvements all the work I have done. I have replaced too many motors for Honda, Nissan, Toyota, Subaru. Never seen it this bad.

I am going to clean and reinstall the old injectors but given how the truck was running before and now I suspect nothing will change. I have inspected the MAF it does not look dirty because if it did truck should not even made it from L. Havasu (a 3 hr drive). Truck does not overheat, it starts right up. Just runs awful and lacks power.
One thing I did not like was that my friend both a naked block from a business in Chicago and expensive. I prefer to buy the full motor so its parts can be kept for testing and/or replacement compared to the part in the old motor.

Thanks for the suggestions

 

[bcstoy]

Intake Air Control Valve ($17 part at rockauto) is another suspect and probably a fairly likely one given you have both lean and rich together.... if it is barely cracked it might not cause issues at high rpm but will at idle, and at low rpm it will cause too rich/lean at high rpm it will cause the opposite.

I did try another IAC did not make any difference. Thus I kept the old one. Thanks

 

[bcstoy]

also listen for a knocking i had a similar thing with the misfire codes i had like 1 3 and 4 codes but anyway it was the 3rd cylinder valve spring so possibly a valve spring?

I will check the LHS head once I try to put the injectors back. I have not inspected this head, it does seem a little noiser than the other side. I did the head gasket on the other side. I also have a set of new injector connectors to fix the broken ones a repair is necessary. Thanks

 

[bcstoy]

random questions, oil pressure? is this a flex fuel Ranger?, does it have the FF module in the fuel line?
try pulling the SPOUT connector/plug. that will limit timing to base 10 degrees.

This is not a flex truck. I don't think it has a module I was looking around the tank area did not see one. It is a 2002. It has a PATS built into the PCM.
Low oil fuel pressure is easy to spot the valve train will rattle badly. I have seen that in a mustang before due to the fact that the valve seal collapse and can get sucked into the oil pump.
Oh, fuel pressure is 60 psi, right on the money

 

[Brain75]

Well then there is also the issue of what condition the donor motor was... I assume you didn't pull a head off and inspect valve train... Seems more than one person recently is seeing valves getting pounded down and recessed to the point the motor leaks like a seive but somehow runs. (those generally are all 4.0's not 3.0's though)

Leakdown check should show you any major issues with the engine.

 

[bcstoy]

That is a good point I have not looked into it. Compression in #2 is lower than the rest I have seen a utube video where I guy found the problem you are describing. I may have to try a leak test. But the motor has compression, except for #2 which gave 120 but the battery was a little low. I had one situation in a rebuilt 22re where compression was low to poor ring installation resetting those did the trick.

Thanks again B75

 

[Brain75]

re-reading the thread to make sure I didn't miss anything...
1st post, you replaced a head gasket, did you inspect the valve seats at that time?

to answer the question you asked but nobody has addressed.... the PCM's usually don't go bad other than the fact the capacitors are now what 22 years old, if it is high mileage (more so than raw age, I am running on original 34 year old now) then the capacitors might have started leaking and going - which it is easy to re-cap them.

 

[bcstoy]

Yeah, they rarely go bad but I have seen that in Nissan vehicles and on Hondas. I did a visual inspection saw nothing unusual. Truck is close to 200K.
I did not inspect the valve seats. Knowing what I know now I should have disassemble the head totally. I know for a fact that the RHS is prone to cracks especially the 2.9. I actually had another engine from a 99 and the head was cracked. I do not even want to talk about the removal of the fan, gosh, problematic. I did develop a trick for it though.

In another note I just started removing the injectors, tested resistance and flow. One of the after market had no pressure. Thus will reinstall the original ones (ford). If that restores the performance it could prove the old pcm quit working.

Thanks for the input B75

 

[Brain75]

We all learn from our mistakes, I bet I wouldn't have thought to really really look either... probably a quick glance, cause that is my habit after getting bit one too many times by not looking everything over before assembly.