fishead

No, pretty sure it is not off a tooth. Like I said, it has been checked a few times. I agree that you can't be too careful, but I am pretty sure it isn't off. Last night when I took it for a burn on the highway, I noticed the oil pressure light come on a couple times when I had the clutch in. I did wet the low cylinder a bit, and it didn't make a difference. I am on my lunch break right now, so I am going to run across the street and talk to my mechanic. I will keep you guys posted as I find stuff out. Chris.

Thanks for the advice guys. I just took it for a burn on the highway and threw in some top grade fuel. Doesn't seem too much different. I will try some of this tomorrow. T-Belt... yeah, I figured the same. My mechanic checked, then I checked. Looks pretty perfect. I tightened it a little bit, no difference.

I was just messing with it, and notice quite a bit of water dripping out of the exhaust. I have it pulled out behind the Cat to see if there was a blockage (I should pull it apart behind the Y pipe next, eh?) and there is a substantial drip coming out of the opening. There is also a drip out the end of the tail pipe. I know water is one of the byproducts of combustion, but how much? It doesn't smell like gas, and isn't slippery. Haven't tasted it... yet. If it looks like my engine has substantial internal damage, there are plenty of local engines available for less then the price of a rebuild. Then I could rebuild this one in my garage.

I can't find any vacuum advance. It seems to be all electronic ('90 VG30E). My haynes manual says that the timing is not adjustable... It runs fine until I rev it up. It hits a certain RPM, then totally bogs and the RPM drops. I pulled the throttle position sensor off, doesn't seem to be that. Thanks for the ideas. Just gonna go pull some more stuff off.

OK, so far this morning I have checked all the wiring I could reach, and pulled at all the vacuum hoses, but nothing changes. I pulled the exhaust off after my cat, and it looks like lots of exhaust is coming out, but doesn't make a difference. Just for good luck I am gonna pull out the air filter... Thanks for the advice guys, but I am just running out of ideas.

I actually read that thread, but was still unsure. Broken piston/headgasket... wouldn't my compression suck? It runs/idles perfect until you hit about 3K RPM. Then it totally bogs down and you can smell raw fuel out the butt end. I pulled each plug one at a time while doing my compression test. They were pretty black. In the past, I have always found a loss of low end with bad plugs. From what I can see, everything is plugged in tightly. I will check more thoroughly tomorrow. Doesn't smoke on startup. Actually, it runs quite well on startup. Maybe I should just put a sparkplug in the tailpipe to burn off all the extra fuel and leave it actually thinking about this... if I do, there WILL be pictures for you.

OK, here's the story. Thanks for reading, sorry its going to be so long. I bought this '90 Pathfinder SE-V6 a few months ago, and put only 3 days insurance on it so I could change the timing belt (260,000KM just want to be safe). I was super careful to make sure I did it right, and took my time. Once I was done, I noticed that it was REALLY gutless. So, I changed all the cheap stuff: Sparkies, fuel filter, air filter, cap, rotor, wires. No improvement. Searching the forums, everyone says "exhaust manifold". I put this off as long as I could, then finally bit the bullet, borrowed a short drill, and called up some buds. 5 broken studs, and we fixed the manifolds. I expected an immediate improvement, but didn't get it. More research tells me that maybe my O2 sensor gave up in frustration. Where I work, we share a parking lot with a fairly reputable mechanic shop. They borrow stuff off us sometimes, and vice versa. Short story, I trust the guys. They said "don't just go replacing stuff. Bring it in, and we'll give you a deal on reading the codes and testing the exhaust." (they said they would only charge for the codes, but throw in the exhaust test). So, they scan the codes, and find nothing. He takes it for a spin, and confirms "severly gutless". He tests the exhaust, and confirms copious amounts of raw fuel, and will definitely fail emissions testing in December. OK, why? MAF sensor? Because he is a mechanic shop, he ordered up a MAF sensor and swapped it in. No difference. Cat? He pulled off the Cat, and said it looks fine. Timing? Knowing that I did it, and I am not a mechanic, (he gave me advice when I did it originally), he pulled off the top cover and confirmed that I have it bang on. Distributor off a tooth? He put a light on it and tweaked the timing. He also tested EGR, temp sensors, throttle position sensor, everything he could think of. He sent me home on Friday and suggested I do a compression test. On the way home, I could not rev above 3K RPM, and have NO power. I have a fairly long commute through the city, and was a little worried about someone getting angry, but managed OK. So, fearing the worst, I did a compression test on Saturday. My lowest reading is 130PSI, and my highest is 160PSI (I have no idea how a "compression ratio" is calculated). OK, so my compression isn't perfectly even, but why the problems? Something the mechanic did is causing it to run worse then before, but what? I think that tomorrow I will see if I can get my cat off and check for blockages downstream or something. If anyone can give me advice, I would REALLY appreciate it. Just now I finished confirming my timing belt, and tweaking the timing myself. I have it bang on 15 deg. One other thing. I am still a few thousand KM away from my next scheduled oil change, and already the oil is BLACK. I noticed that right from when I first got the truck that the oil goes black real early. The antifreeze was a nice brite Kool-aid green as well. Mmm that stuff looks tastey. And the neighbours dog that barks all night... just kidding. Thanks everyone. chris. (long time lurker here, I love this site)

This is too funny. I just got in from pulling out my last broken stud. My advice, find a machinist friend and make him help you. (don't give him beer until he is done though) I borrowed a nice 90degree Makita drill from work, and using a mirror, we were able to drill a 1/8" hole in each broken stud, and work them out with an easy out. If you cannot find an anal machinist that will absolutely make sure to drill exactly in the centre, it would prolly pay to have someone do it. I wanted to pay to have it done, but it was just too much. I was quoted $400 to just change the gasket. If there were any broken bolts, it was going to be extra!!! 5 broken bolts later... I am putting the manifold on right now, but in 6 months (income tax time) I plan on headers. Due to emissions testing in my city, I guess I better stick with a header that has an egr connection, eh?