Swapped The Clutch, Now Getting A Hesitation?

[jj big shoe]

87 V6 5-speed

 

I finally got my Pathy back on the road a few weeks ago. I drove it to Tampa and back (100 mile trip) and when I pulled onto my street I heared the tell-tale sound of a throw-out bearing going kaput. I pulled the trans and swapped the clutch last week and now its hesitating every once in a while like its not getting fuel for a second or its mis-firing. I can't tell whether its fuel or spark related.

 

I've changed plugs and wires

The cap and rotor have about 2,000 miles on them and I've cleaned them as well

Cleaned the air filter

Checked timing

Replaced fuel filter

Fuel pump is about 6 yrs old

 

The thing that keeps bugging me is it didn't sputter before I dropped the trans so could it be an O2 sensor problem?

The sensor wiring runs over the trans so I moved it around a bit I'm sure.

The wiring wrap is crusty and melted a bit

I've never replaced it, has over 80K on it.

I have an exhaust leak before the sensor at the flange and put Permatex Ultra Copper on the gasket to try and seal it (it said sensor-safe, though)

 

 

I haven't had time to check codes, listen to the fuel pump, clean MAF, etc. That'll all get done this weekend.

 

Anyway I'm wondering if I did have an intermittant O2 sensor problem due to shoddy wiring or whatever, what would the symptoms be?

 

EDIT: After reading up on how the O2 sensor works, I'm leaning toward a wiring problem since the ECU constantly monitors the signal and adjusts accordingly. If the wires are occasionally shorting or open that would cause a sputtering/hestating, wouldn't it?

Edited April 8, 2010 by jj big shoe

[Nismojunky]

have u run the codes?

[jj big shoe]

have u run the codes?

Not yet. I'll have time this weekend but its pretty intermittant. I don't know if any code would be logged. Plus any time I've ever had a problem there haven't been any codes so it ends up sucking time and pissing me off. I'll run them, though.

[Precise1]

Just for peace of mind, check the electrical connections you have to undo to pull the tranny. Yeah, all of them...

 

The O2 sensor shouldn't make it hesitate, just run rich. What is the mileage like, notice any significant drop?

 

Sorry, but it sounds like you are going to have to do the standard trouble shoot; nothing you said sets off any alarms.

 

B

[RedPath88]

While checking the connections, don't just make sure they are correct and tight, but also check for water, grease or other fluids that might be causing problems with them.

 

Make sure the connections or wires into the connectors did not come loose at the firewall/fenderwell for the O2. Might also check them at the sensor. You mentioned that it was melted? Check to see if the bare wire is exposed there.. perhaps it's just shorting out.

 

 

And check those codes, sucks I know, but...

 

 

[jj big shoe]

Damn you and your logical conclusions, B!

I was thinking that if the O2 sensor voltage was to suddenly drop or go to open loop mode as if the sensor was cold it would make the engine run rich and bog a little during the switch.

[Precise1]

Hey, anything is possible but not what I am used to hearing...

 

Just keep at it man, you can figure it out!! You owe it to the skid plate...

 

I need to make a set now that I have a straight pathy.

 

B

[JamesRich]

First check to make sure you didn't pinch a wire between the bell housing when you put the trans back. I have seen this happen alot. It will cause all kinds of ghost to show up.

James

[jj big shoe]

Funny thing is, I drove about 150 miles today and it only slightly hicupped once. I'll take a good look at the wiring while I'm fixing the exhaust leak this weekend. BTW, I forgot to mention in the first post that I'm on the third full tank of gas and I put injector cleaner in the second one.

[Nismojunky]

150miles to three tanks of gas im betting your o2 is done

[adamzan]

Just for peace of mind, check the electrical connections you have to undo to pull the tranny. Yeah, all of them...

 

The O2 sensor shouldn't make it hesitate, just run rich. What is the mileage like, notice any significant drop?

 

Sorry, but it sounds like you are going to have to do the standard trouble shoot; nothing you said sets off any alarms.

 

B

Yeah the o2 if it is bad sometimes will make it hesitate. It did that for nige's truck and mine.

[jj big shoe]

150miles to three tanks of gas im betting your o2 is done

That's like 3mpg. I think the M1A1 Abrams gets about that. I was saying I've put 3 tanks thru the system since I got it back on the road after about a year so I wouldn't think it had to do with bad gas or condensation.

Edited April 9, 2010 by jj big shoe

[jj big shoe]

The road test will be tomorrow, but I think I found the problem. Looks like the wires to the O2 sensor laid against the headers and melted some insulation off. I assume it would flop around from vibration and wind and short to the body or trans and give inaccurate readings. I cut the bad parts out, spliced new wires in and rerouted them away from the exhaust. I'll know its fixed after driving it a few days and post again.

[Precise1]

Even if that doesn't fix it right off of the bat, I can't see it hurting.

 

I had a wire ground on the headers right after install, it cut out my entire gauge cluster and put the tranny into limp mode. Limped back home, asked for help, replaced the wiring at that point, tied it back and replaced the blown fuse. Runs fine now...

 

B

[jj big shoe]

Well, it did the sputter-sputter yesterday so I guess I still haven't found what's wrong. It does seem to be less frequent now, maybe there's some goop in the fuel system that's slowly finding its way out. One 3 second hiccup in the last five days or 500-600 miles doesn't really make it to the top of my worry list right now so I'll concentrate on finishing a few other things and get back to it later (if it doesn't correct itself). Thanks for the input and I'll post the solution if I find it.