Sir Jeep-a-Lot

OK guys, my '93 was sputtering and stalling right when I bought it a few months ago. I did a bunch of work on it since and is definitely not stalling anymore, but it does still have an occasional sputter/misfire sometimes when I'm accelerating through 2nd or 3rd gear usually...sometimes 1st. It was kind of bad today and jerked the vehicle pretty good a few times (not cool on a busy road).

I've replaced most of the usual suspects for this type of problem, but it still has that dang hiccup. I just don't know enough about engines to be able to pinpoint it, and I'll be driving it across the US in a few weeks...so any suggestions at all are greatly appreciated!

Oh and it is also having some trouble starting up right away. It takes longer than normal, but it always starts...sometimes I have to give it a little gas. Could be related to sputtering?

Here is what has been done so far:
- replaced CPS (autozone)
- full tune-up: plugs, wires, cap, rotor (Accel), air filter (?), fuel filter (WIX)
- changed oil & filter (Pennzoil, Fram)
- cleaned throttle body
- changed fuel pump (Bosche)
- new battery (Interstate Mega Tron Plus)
- added Lucas fuel injector cleaner
- bypassed fuel pump ballast resistor

ksan0311

What kind of gas do you use?

I know in my jeep if i use anything higher than 89 my engine sputters (and backfires sometimes)

Sir Jeep-a-Lot

Just 87

Sir Jeep-a-Lot

Ok, playing the process of elimination game here...I'm almost thinking it may be an ignition system issue, since I've already replaced most parts in the fuel system. New fuel pump & filter, removed the ballast resistor, added fuel injector cleaner...anything I could be missing? Haven't checked fuel pressure since putting in new fuel pump, but I will do that soon just to double check.

It's also having a little trouble starting too, though it always does start up. Thinking I should check the ignition coil? My exhaust manifold has a good-sized crack above the O2 sensor...think that could be affecting the sensor? Any other ideas?

It has this hiccup every time I drive now...usually while in the lower gears. My driveway is VERY steep and it ALMOST stalled twice at the steepest part!
...not cool.

RTorrez1

I know that you put a lot of time and a few bucks it to her. But you should have bought your CPS from the dealer. ALL the others a garbage.
The plugs if you are saying you put the Accel. That can be part of the sputtering problem. Use Champion plugs. I put Bosch in mine and it ran like crap.
And for the Fram oil filter. Get rid of it as soon as possible. You want to use Mopar or Wix.

ZINGGG

I'm going to have to agree with this. For the most part at least. You DEFINITELY want to get the Fram filter off. That's your first step. Wix is a good filter.

Those plugs should be okay as long as they are copper. And as long as they are gapped correctly. Did you make sure to gap them to .035? If not, pull them and gap them.

Your Autozone CPS will probably not last all that long, just as a forewarning. That is a part you want from the dealer. I don't think that would cause a sputter though.

Another step for you to take that is nice and free, refresh all your grounds and your battery terminals (if you didn't do so when you put in a new battery).

Sir Jeep-a-Lot

Hmm OK, I'll get a different filter asap. Can the oil filter really make that much of a difference? And I need to drain the oil to change the filter, right?

I think my plugs are copper but not really sure...gapped them, but just tightened by hand since I didn't have a torque wrench. Anyone have experience with Accel spark plugs? Maybe I will try to get some Champions if you say those are good, just to eliminate that possibility.

And I guess I will just get a quality CPS if I can afford it, too. In the FSM, I thought it showed some sort of spacer for the CPS...but mine didn't have one. Does anyone know if this spacer thing is necessary? Gotta love the CPS...can't wait to bust out the ol extension set and crawl back up under there! LOL Got to stop shopping at Autozone & O'Rielly's...

Oh and I cleaned all the grounds and battery terminals today...we'll see if that helps any. Thanks for the replies.

Sir Jeep-a-Lot

Cleaned all the grounds yesterday and took it for a test drive today...in an hour of driving, the engine only slightly cut out ONCE. And that was when I pulled out of my driveway accelerating in 1st gear. Accelerated pretty hard up to 60 MPH and couldn't feel it cut out at all. seems cleaning the grounds helped quite a bit!

Guess I'll just keep dialing it in and maybe it will be 100% hiccup-free one day haha.

jomps

fix your exhaust manifold, the o2 sensor is reading the mixture wrong

Sir Jeep-a-Lot

ok thanks, gonna order new headers this week It hasen't been hesitating or bucking at all since cleaning the grounds, but I definitely notice a loss of power because of the cracked manifold...

BlueBird 4

Hey Man, I'm having the exact same issue.
Did yours finally stop bucking / Sputtering?
If so, what finally fixed it?

I've done:
CPS
TPS
Spark Plugs
Spark Plug Wires
Lucas Injector Cleaner
Seafoam in the gas tank

I worry about the copper wire thing.
Mine are not copper

Sir Jeep-a-Lot

No, not completely....have you checked fuel pressure? Gapped the spark plugs correctly? May be the fuel pump and/or fuel filter. I would definitely do that first if I were you, or just change out the fuel pump and filter. You could also bypass the fuel pump ballast resistor; quick & easy to do and it is not even needed, might as well eliminate that possibility. My new Bosch pump is even quieter WITHOUT the ballast resistor lol. If you need a new pump, do NOT buy an Airtex! Probably a good idea to clean your engine grounds as well.

I just recently noticed that my engine usually only cuts out when making RIGHT turns....anyone have any ideas on that? Gonna check my fuel pump wiring to see if something is shorting out...also ordering new headers today and getting different oil filter.

EDIT: engine ONLY cuts out when making right turns AND low on fuel...filled up and no problem.

EDIT AGAIN: I just read here that the fuel pump strainer acts as 1) a fuel filter and 2) a little resovoir so that the fuel pump won't be starved when low on gas and going around corners. And I noticed the new strainer was a little loose fitting on the fuel pump assembly when I put it on....I'll bet it fell off in the tank or something. Guess I gotta pull the pump again

Sir Jeep-a-Lot

ummm, why are there 2 or 3 pages missing from this thread?