Recent content by @dam

I'm traveling for work and such. Don't have the time and tools to troubleshoot, so I took it to a transmission shop. They figured it out. Charged $200, but hey...it's CA

It was the clutch PEDAL that broke. Who'da thunk?

Hi all. I'm out of town on the start of a 2.5 month trip. Tonight I was driving home. At a stop, I pushed the clutch in on my '95 4.0 and heard something pop/snap. At the stop, I stalled. The clutch seems to be fully engaged all the time, and the pedal doesn't come very far off the floor...

I read that if wet compression was higher than dry compression by over 10%, your rings are considered bad

It's the miss at idle that makes the exhaust emissions high, and since I've replaced everything but the coil and CPS on the ignition side, and have new injectors on the fuel side, that's what I'm left with: badness with either my piston rings or valves, and it's looking like rings except...

I just got back from a 2 tank road trip...rural highways in New Mexico. I got 23.2 and 25 mpg- my best ever. I don't get why my mpg is so good if my wet vs dry compression numbers are so different. I'd love to drive the wheels off it, but if I can't get it by emissions without a rebuild, I...

Hmmm...it drives great except for the miss at idle. What's the ballpark for a rebuild? I'm doing this solo so didn't see the first crank pressure, but I'd go back and forth and it'd take quite a few cranks to level out.

1995 4.0 with 233k highway miles. Oil changed every 3k for most of its life. Power up a particular hill near me has been the same for the last 10 years. It gets about 21 mpg and has for a long time. It has had a slight miss at idle, and has for years, but it baaaarrely squeaked by emissions...

I forgot to mention I'm at 6000' altitude. After correcting for altitude, my compression numbers are... 147 138 147 144 152 147 Not bad for a cold engine- it still has life left. I'm thinking that low one is probably a sticking valve, so perhaps I'll run some top end cleaner through it...

Wait...I think I figured it out. It has to do with the specific heat of air. P1*V1^y = P2*V2^y where y is the ratio of specific heat for air. So, (P1*V1^y)/V2^y = P2 y = 1.4 P1 = 14.7 psi V1 = 43.48 ci V2 = 3.48 ci So 509 psi is the maximum theoretical pressure in an ideal, perfectly...

It seems like, with a 9.2:1 compression ratio, it'd be 9.2x atmospheric pressure. 9.2 * 14.7 psi = 135. That seems low though. Someone on another thread said 175 psi, but wouldn't that require a much higher compression ratio? How would you get more than 9.2x of whatever you have to work with...

Any word on an aftermarket manifold that's no-kidding bolt-on? A lot of the reviews I'm seeing talk about having to dent, grind, and fab up spacers etc. to get them to fit. This Amazon one seems to be a good deal. https://www.amazon.com/91-99-Wrangler-Exhaust-Manifold-Gaskets/dp/B001O9ZJT8

FullSizeRender 11 by Adamandshawn, on Flickr

Oh...I think I have a crack on the weld of the exhaust manifold. How do I post a pic?

Well, after driving for a few days I think my initial assessment was wishful thinking. It's definitely not 70% better. I suppose the only thing left on the ignition side of the house is the CPS and the coil, and on the fuel side it's the FPR and MAP sensor.