Running crappy after tune up?

[JTH1972]

Ok, so here's the story...

Around a week ago, I changed the plugs on the truck. It ran good with no noticeable problems. Around last Thursday, I changed the plug wires, cap, and rotor, and pressure washed off the motor to get rid of all the built up oil on it. The first thing I noticed was that the truck would run decent in a high idle, but the motor would start to shake and sound like it's missing at a lower idle for around 20 seconds, almost stalling, then reving back up into a higher idle.

While driving it, the truck didn't seem to have as much pep as it usually did, and it would really bottom out and start to sputter when going up hills, until it got into a higher RPM range, It would do the same thing on flats on occasion too. This lasted for a couple of days. Fuel consumption to me seemed to be higher. However while driving the truck yesterday, everything seemed to be as right as rain. Fuel consumption is still questionable, but I am still learning the truck.

I thought that maybe I got something too wet when I pressure washed it, but I would assume that it would be running like crap all the time instead of just occasionally? Could i have created a vacuum leak by blasting off oil that has sealed something before?

Any ideas would be appreciated.

 

[The Fox]

I am having the same problem as you are.

Here is a thread I started that has many suggestions as to how to solve it.

http://therangerstation.com/forums/showthread.php?t=30027
Nick

 

[gertsdsbs]

It needs a Tune-up, Tune up!

 

[JTH1972]

So far today it's been running good. Fuel consumption is a little hard to gauge since my fuel gauge has been bouncing back and forth. I'm still going to check through the thread and see what others have suggested for ideas.

gertsdsbs, care to elaborate? The more I can do myself, the better.

 

[KCBFord1]

maybe the fuel pressor regulator/diaphram has a hole in it and the vacume lines are sucking in gas from the injector rail?
thats what mine was doing.

So far today it's been running good. Fuel consumption is a little hard to gauge since my fuel gauge has been bouncing back and forth. I'm still going to check through the thread and see what others have suggested for ideas.

gertsdsbs, care to elaborate? The more I can do myself, the better.

 

[JTH1972]

That's one of the things I'm going to check today, as well as try to get the fuel filters changed. I'm going to be installing a MSD coil too. I bought new battery cables too since the ground one looks like it's original and corroded to all hell.

 

[JTH1972]

OK, so I installed the MSD coil and new battery cables this weekend.
First drive, it bogged down on the first hill, then seemed ok for the rest of the hills (computer re-learning?). Later on I had it on the highway, and it was running really crappy in OD. It seemed to do this in a higher gear/lower RPM range. It also didn't seem to matter if the engine was warm or cold. When it does bog down, most of the noise sounds like it's coming from the passenger side of the motor.

Any thoughts?

 

[dgndngrngr]

well most of the vacuum conections are on that side. i had a similar problem untill i put two fat screws in the vacuum lines runing into the bottom of the airbox. seem to me that the problem was fixed but havent got it over 55 yet. here some spots to check:
vac lines at the box below the airbox
map sensor vac line
green vac line to the egr
vac line from the FPR(fuel pressure regulator) to the intake

wouldnt hurt to check the idle air sensor on the passenger side of the intake manifold on the top. actually check any of those tubes going into the intake near throttle body too.
lastly spray some intake cleaner in the throttle body and you hold the throttle partially open. this will help clear out the crap you cant see in the attached vacuum lines.
hope this helps. keep us posted

 

[JTH1972]

well most of the vacuum conections are on that side. i had a similar problem untill i put two fat screws in the vacuum lines runing into the bottom of the airbox.

Funny you should mention that... usually when I turn it off, I can hear something vibrating, like a rubber flap, around or under the airboxthat lasts for a minute or so, and then dies off like a balloon losing its air. Is that the vaccum lines?

seem to me that the problem was fixed but havent got it over 55 yet.

Usually I can get it up over 55 (90 km) no problem, but today, not a chance in hell! Going into the first town was ok. I had stopped for a little while (maybe 20 minutes) and then had a hard time starting the truck again after that. Going on the highway to the main city was a chore. I couldn't get it over 90 km and it fought me the whole way. No power or acceleration, and every once in a while it would give a "kick" and shake the whole truck. I usually have the problem in OD, so i tried dropping it down to drive to see if it would make a difference, but it didn't. I stopped at the first light in the city, and something like a lifter was knocking pretty loud under the motor, again from the passenger side. The motor knocks some as it is but I usually don't hear it in the cab. Barely any acceleration from that light to the next one. By the next light, the knocking has subsided, and the acceleration was better, but no where near as good as it was earlier in the day.

wouldnt hurt to check the idle air sensor on the passenger side of the intake manifold on the top

I replaced the IAC sensor recently with one I found in the junkyard. It was a lot newer looking than the original one I has on there. The gasket fit a little different on mine that the 88 it was on, so i plan on remaking the gasket. Of course, I didn't have time to fix it today before I had to go.

actually check any of those tubes going into the intake near throttle body too.

some time in it's life, someone removed the hard line that goes from the throttle body to the carbon (vaccuum?) cannister that's by the drivers side of the radiator. I think it's just part of the emissions

 

[dgndngrngr]

its possible its those airbox lines on yours too. one of the 2 has a very strong vacuum. try pluggin one or both and drive it for a bit. i just drove mine again today but still under 50 and it was ok so may or may not be the fix.

it sounds like we both have the exact same problem.

do you have an aftermarket oil pressure gauge? if so what does the pressure read. i get a real loud engine knock at idle that almost drowns out the lifters and this happens after it warms up and the oil pressure drops below 20psi

also have you had trouble starting it before? like have you run it for a while, shut it off and it wont start again? because this sounds like the ignition

i still think and hope that if you plug those 2 vaccum lines that takes care of it. my truck has an 86 (i think) reprogrammed computer with a 91 (i think) engine and 86 engine and vacuum wiring. all because of several engine swaps so my computer still thinks things are there (egr, etc.) when they are not.
let me know what you find

 

[dgndngrngr]

also try pulling the codes: http://www.therangerstation.com/tech_library/OBD_I.html
this will help narrow down whats goin on

 

[JTH1972]

Thanks, I'm going to do that tomorrow, providing i'm not coughing up a lung!

Ride home tonight wasn't great. Idle felt a lot rougher than usual, but it wasn't missing. Had a hard time getting it over 80km (50 miles). it definitely didn't want to be in OD. Bucked and shuddered like crazy in the higher gears (auto tranny, AL4D I believe). Mind you it was tempermental in Drive too.

Any idea of what those airlines going into the box are supposed to do?

It's frustrating. The more money I put into it, the worse it runs!

 

[JTH1972]

Okay, I just did the KOEO test and it flashed 11 twice, long pause then one pulse (seperator), another long pause, then it flashed 34 twice, which according to the codes is:
EVR - (O, R, M) EVP sensor is/was high - EVR
PFE - (O, R, M) PFE sensor is/was out of range - PFE

I'm not familiar with the acronyms, so can someone help?

KOER Test as follows:
1 pulse
light flickered
21 - Engine Coolant Temperature (ECT) sensor out of range - ECT
33 - ALL - (O, M) EGR did not open/ respond during test or if memory code, did not open intermittently - EVP EVR PFE
77 - System did not receive "goose" test - see TESTS
25 - Knock sensor not tested (ignore if not pinging) - KS
21 (repeated)
33
77
25

Translation help please? So far from the KOER test I'm going to have to replace the EGR valve and coolant sensor, correct?

So I also figured out why it's been running so crappy... for some reason, my #5 Spark plug wire is gone! Spark plug is still there, and the boot was left on the distributor. No idea how or why.

 

[JTH1972]

So, looks like all this time my problem may have been a bad (although new) spark plug wire. I used a spare coil wire as a substitute spark plug wire until i could get into town, and it ran flawlessly. Bought a replacement wire and did some driving around, and it worked fine.

Go figure.