'93 bogs on incline (1 Viewer)

[alkaline747trio]

When on an incline my friend's '93 with 140k will miss if in park and smell like it is flooding. If in drive, it will miss, shake, bog down and cut off. All of these symptoms occur off-road/low speeds. I have no clue about service records etc., but it has had a missing problem for about a year, not a DD....maybe 1k miles in a year. It is starting to become his DD, so he wants to get it fixed soon. Any help would be great.

 

[Beowulf]

Is he throwing mis-fire codes?

Might be a clogged fuel filter. Seems like Junk had the same problem and fixed it with a new fuel filter.

-B-

 

[alkaline747trio]

No check engine lights or anything, and you can smell the gas (flooding). If parked on an incline, you have to keep it floored to keep it running and RPMs never go above 1000.

 

[Bear80]

check your spark plug wires.

 

[powderpig]

Wiring harness next to the EGR pipe, chck it for melted wires. Pull the plugs and see if you have a bad spark plug. check for vacuum leaks. When was the last tune up? Check compression. GIf you have a FSM there is a great trouble shooting chart that clues you into what may be wrong with the symptoms you have, even give you number 1 casue then on down the line with other causes and how to trouble shoot it. later robbie

 

[sleeoffroad]

Check the intake house that runs from the filter to the throttle body for cracks.

 

[fj803fe]

Check the intake house that runs from the filter to the throttle body for cracks.

Second that. The incline may move the engine away from the filter box enough to exaserbate a crack in the air intake hose. You could duct tape all around to verify. I'd pull off and inspect carefully-sometimes these buggers are minute and hard to see inside of the acordian bends.

I just assume you are talking about the air intake hose Christo-the problem sounds superficially similar to what would occur with such a crack.

 

[alkaline747trio]

Ok I went and tested it this morn. Tested once before it got warmed up and it did not stall out. But after it got warmed up, I tried again and it bogged, cut off, and DID throw codes (solid oil and check engine lights, no blinking in either). What should I check? All hoses and wires looked good.


Edit: for friend's poor typing skills.

 

[Bear80]

so it smells like it is running rich? and runs as long as it's not idel in park? I would really make sure you are getting spark to every plug. Get another set of wires on it.

 

[alkaline747trio]

The wires looked almost new, and if on a decent incline, in drive it will cut off no matter what you try, in park, if you keep flooring it, it will stay running but smell like it is flooding (of course due to flooring it). If it is the intake, why would the crack cause this problem? I will tell him to check that out too.

Summary: lack of spark (wires?) or leaky intake (crack in housing?) would cause this? Anything else?

 

[fj803fe]

The wires looked almost new, and if on a decent incline, in drive it will cut off no matter what you try, in park, if you keep flooring it, it will stay running but smell like it is flooding (of course due to flooring it). If it is the intake, why would the crack cause this problem? I will tell him to check that out too.

Summary: lack of spark (wires?) or leaky intake (crack in housing?) would cause this? Anything else?

I can't necessarily say with confidence as I am not certain where the MAF sensor is on the 1fz, but if the crack is post MAF sensor-air flow/fuel mixture reading at the CPU will not reflect actual air intake resulting in poor air/fuel mixture.

I don't logically see how it would default to rich from such a problem-but I had the same problem/fuel smell after a flexy obstacle in Moab that finally made my hairline undetected fault turn to a crack through the hose from the frame/body/engine movement-oh yeah and a seperated drivers side engine mount added to the "movement" situation as well .

 

[fj803fe]

But shes okay and newly rubbered now...in case you had LC concern syndrome

 

[Bear80]

The wires looked almost new

Looks doesn't mean anything. You can have a small crack in the rubber boot allowing the spark to jump out and never reach the plug.

Logic......if it is running rich then obviously you are not getting ignition. Hmmm.......that would mean spark.

Added: I would agree that unaccounted air will cause some issues. However you would have a very noticeable hole to let enough air in to kill the engine.

 

[alkaline747trio]

He took off the spark plug cover and looked over the wires, I guess I will have to follow behind him and look over it more thoroughly for him. Should I take the wires all the way out, or would a once over while still on the engine suffice? (plug end out obviously, but still on the distro and in the clips and everything)

 

[Stevemcnash]

If it only does this on an incline, then I doubt it would be the sparkplugs, although they should be checked none the less. My money's on a clogged fuel injector or maybe the crack that people had mentioned earlier. And it only does this on an incline? On flat ground runs fine? No smell, no missing?

 

[Bear80]

I had almost the exact same problem on my 22re. It would come and go, usally after/during running down some bumpy roads, or wheeling. My wires looked "new" but they had an extremly corroded contact and the spark was jumping out of the boot.

Oh and it would start even just ideling in place, so I'd say incline, decline flat doesn't matter. Now this is all one your account that you say it runns with a bad miss and smells rich.

 

[alkaline747trio]

It doesn't run with the bad smell or miss, just when on an incline it will start to bog. Now that I think about it, it isn't much of a miss (he just kept saying it missed). It doesn't do it on a decline or flat ground. Just on an incline will it bog down and then will smell of gas (from keeping it floored to keep the engine going, no smell if you just let it die).

 

[CreeperSleeper]

I don't know if this is will work, but I know that my VW will do stuff like this with vaccum leaks. I would put money on something along that route. I could be wrong, but I would think that everything else would be less "incline specific". Does it bog out at WOT on flat ground?

 

[Stevemcnash]

I would think that everything else would be less "incline specific". Does it bog out at WOT on flat ground?

That's my thoughts too. All the causes that I can think of aren't specific to bog down on incline. If it was flat ground too, then some of the ideas we've come up with might be more valid. We know that what ever the cause is, it changes with the angle of the car. After thinking a little more, I doubt it would be the fuel injector, if it was smashing the peddle would stop the bog down. But if you smash the peddle and you only get to 1k RPMs then it's gotta be some ignition problem. Some how only on an angle the car can not use the fuel right. I don't ..... Hope my rambeling didn't throw anyone off now

 

[CreeperSleeper]

I see what you are saying, my thought is if you stomp on the gas on flat ground from a dead stop and it hesitates or bogs down, then a fuel filter or pump could very well explain it. If it is under normal driving situations on a decline or flat ground, it may be getting enough fuel. However, the fuel doesn't have enough PSI to feed the engine on an incline. The smell of gas would be from it "pooling up" in the lines. I don't know why that happens, but I know it does.