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Feeling weak (rebuilt 4.0, 4.56, AW4, 31s...), Why?

You're the only person here who's ever used the phrase "dialing it in".

We're talking about a glorified tractor motor that appears to not have a timing problem, so if you would kindly, quit yammering on and let us get back to the OP's problem.
 
cal said:
You're the only person here who's ever used the phrase "dialing it in".

We're talking about a glorified tractor motor that appears to not have a timing problem, so if you would kindly, quit yammering on and let us get back to the OP's problem.
Click to expand...

I'm the one that said he had a tuning problem I'm also the one who said he does not have a timing problem

I believe it is you who has the issue
 
notamos said:
For diag "tools", I have a timing light and Torque on my phone. Any basic tests you could recommend?
Click to expand...
I am not familiar with that app. Can you cruise around and see if the ECU is in open, or closed loop?

So far, Trippled has given the easiest, and cheapest advise. If you find something, you find something. If you don't find anything, you can push controls to the back burner while looking at the mechanical aspects.

Something like this could make for a good Chapter Tech Day, if we can talk old_man into it. ;)
 
Jeep Driver said:
I'm the one that said he had a tuning problem I'm also the one who said he does not have a timing problem

I believe it is you who has the issue
Click to expand...


:wstupid:

It is unfortunate this thread has gone this way.

To the OP....checking vacuum, compression, valve timing, and valve lift are all free assuming you have the tools (or a friend). Regardless of what anyone has stated here, those items are worth checking.
 
whitexj98 said:
Have you driven an XJ much before? Or have a buddy to compare? Feels slow can be a pretty relative statement depending on your expectations. I mean my XJ is a dog compared to my turbo regal...lol
Click to expand...


Yeah is there a baseline you can test it off? Also did you say you're at 6k elevation in colorado? (or did I read that somewhere else?)

Also mine feels quick(ish) with stock 3.55 gears and 30" tires and if I'm not mistaken you should get a more torquey feel off the line with numerically higher gears but the car won't go as fast.

I'm really wondering if you're expecting to much? stock 0-60 times on that are like 10 seconds. that's pretty slow and with an NA at 6k feet it's going to be slower
 
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Nah, I'm not chased off. I got busy with the kids sports practices and haven't had a chance to look at the XJ.

To answer some questions:
-I did reuse the stock injectors. One of the few parts I reused.

-I do have something to compare it to. I've owned a 88/4.0/5-speed w 3.55s and 32x11.5s, a 99/4.0/aw4 w 4.10s and 31s and now this 99. My last 99 would have killed this one 0-60, with it's 4.10s.

-I do have the full version of Torque. Hope to get it out tomorrow for a bit of driving.

-I may get together with some of the chapter guys on Sun to look at things (compression, leakdown, etc).

-Yes, I am in CO at about 6k feet during normal driving.

-This thing seems like it runs well. No rich smell, fires right up with no odd noises, revs quick/high, has never thrown a code.

Now, calm down boys and look at these pretty pics of the engine in question... lol.

IMAG0073.jpg


IMAG0078.jpg
 
notamos said:
Nah, I'm not chased off. I got busy with the kids sports practices and haven't had a chance to look at the XJ.

To answer some questions:
-I did reuse the stock injectors. One of the few parts I reused.

-I do have something to compare it to. I've owned a 88/4.0/5-speed w 3.55s and 32x11.5s, a 99/4.0/aw4 w 4.10s and 31s and now this 99. My last 99 would have killed this one 0-60, with it's 4.10s.

-I do have the full version of Torque. Hope to get it out tomorrow for a bit of driving.

-I may get together with some of the chapter guys on Sun to look at things (compression, leakdown, etc).

-Yes, I am in CO at about 6k feet during normal driving.

-This thing seems like it runs well. No rich smell, fires right up with no odd noises, revs quick/high, has never thrown a code.

Now, calm down boys and look at these pretty pics of the engine in question... lol.

IMAG0073.jpg


IMAG0078.jpg
Click to expand...

Thanks for the pics.

By all means, do whatever testing you find necessary. But, I'm more convinced now that you'll find your problem to be sensor or injector related.

If it were mechanical, you'd have other symptoms, obvious ones.

11mpgs is the dead give away.
 
notamos said:
Nah, I'm not chased off. I got busy with the kids sports practices and haven't had a chance to look at the XJ.

To answer some questions:
-I did reuse the stock injectors. One of the few parts I reused.

-I do have something to compare it to. I've owned a 88/4.0/5-speed w 3.55s and 32x11.5s, a 99/4.0/aw4 w 4.10s and 31s and now this 99. My last 99 would have killed this one 0-60, with it's 4.10s.

-I do have the full version of Torque. Hope to get it out tomorrow for a bit of driving.

-I may get together with some of the chapter guys on Sun to look at things (compression, leakdown, etc).

-Yes, I am in CO at about 6k feet during normal driving.

-This thing seems like it runs well. No rich smell, fires right up with no odd noises, revs quick/high, has never thrown a code.

Now, calm down boys and look at these pretty pics of the engine in question... lol.

IMAG0073.jpg


IMAG0078.jpg
Click to expand...

there is the problem......It,s a Kubota Tractor engine,,,:D
 
1) Great looking engine

2) Ok so you do have a baseline which is good.

3) If the injectors are gummed up and not providing enough fuel that would hurt it but the fact that it's clearly using fuel (11mpg seems to be burning through a decent amount) means they SHOULD be fine. though (and more to my point) if it's a stroker wouldn't you want higher flowing injectors anyway as with higher displacement you want more air and fuel (not really figuring this is your problem just a side thought) either the neon 4 holes or ford 6 hole injectors?

Edit: Misread that thought it was a stroker so ignore that part about the injectors. you wouldn't really require higher flow injectors. Though I am hoping you cleaned them up before you put them back in?
 
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Derp!
 
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clydefrog said:
Dont know if I missed it but how does the catalytic convertor look? Have you checked exhaust back pressure?
Click to expand...
IIRC, it has a new, 2-1/4 inch exhaust.

notomas said:
-I may get together with some of the chapter guys on Sun to look at things (compression, leakdown, etc).
Click to expand...
old_man has a vacuum gauge, and he knows how to use it. :)
 
Just because a cat was new doesn't mean it's good, especially after 14k miles if it's been overly rich. Get a shop to do back pressure on the cat but if it free revs quick it's probably not the issue. Some sensors are designed for high altitude, same with computer tuning, at least with various other vehicles.
 
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