'99 Vehicross Engine Knock / Engine Replacement Suggestions

[Flurry_Chris]

Hello Everyone,

It's been a long time since I have been on the forums. I have/had (sold to my father) a 99 Vehicross which started to have a rod knock right at 60,350. This happened years ago when it would have still been under warranty but they said since it's over 60k miles they couldn't fix it.

My father has had it for years now planning on redoing the engine but he hasn't gotten around to it and I just wanted to ask you guys what do you think the best way would be to go about fixing it? I saw some posts from before but I was wondering what the most up to date information would be.

-Same engine or if there is a better engine that could be swapped without real modifications.

-If there are any other procedures that don't require a full engine swap that could be tried.

-Any other things that should be checked before this is done.

-And if anybody knows of a replacement engine somewhere around Las Vegas

Thanks in advance and if I've missed a similar post please direct me to it. I just want to get as much info together as possible to help get this done for my father. It's a shame for it it be sitting in the garage and everything else on the vehicross is great.

(I don't know if there are any old members on here but I was at the one VX meet in St. Charles, IL many years ago and I had just picked up the VX at the time but couldn't drive it because of a lic plate issue)

[VX KAT]

Unfortunately there's been several that developed this problem and blown.
There's been several suggestions on what to do.

There's also some debate as to what exactly causes it, some say it's related to the PCV failing, oters say it's from the piston ring design, plus other thoughts too.

The Isuzu Axiom engine (from '04-?) is supposed to be an easy replacement and does not have the oil consumption issue that many of ours did/do. I can recall one guy did the swap (iamironman). An Axiom engine should be pretty easy to find in a salvage yard to replace yours.
He's since sold his but here's his info on it:
http://www.vehicross.info/forums/showthread.php?t=15156&highlight=engine+swap+axiom


Several others have replaced their engine, I'm sure some of them will chime in here.

Here's a post with lots of discussion about the oil issue, and theories on what causes it.

http://vehicross.info/forums/showpost.php?p=216316&postcount=7

[Flurry_Chris]

VX KAT,

Thanks for the response. I didn't realize that the oil consumption thing was a big issue. That is what happened to mine too. I had changed the oil in it and around a month and a half later I checked the oil and it was showing up as almost empty. It was really weird because it wasn't leaking out and I didn't notice any darker color or think smoke from the exhaust.

I'll check into the Axiom engines too.

Thanks,

[VX KAT]

VX KAT,

Thanks for the response. I didn't realize that the oil consumption thing was a big issue. That is what happened to mine too. I had changed the oil in it and around a month and a half later I checked the oil and it was showing up as almost empty. It was really weird because it wasn't leaking out and I didn't notice any darker color or think smoke from the exhaust.

I'll check into the Axiom engines too.

Thanks,

That's a real common scenario in many of these failures. Many believe when there's no dripping, and no burning (smoke out the tailpipe) , that it's often related to the PCV valve. PCV =Positive Crankcase Ventilation, it's part of the emissions control system, but if it gets stuck (open IIRC), it allows the oil to be kind of sucked out.

When the oil is lost through the PCV valve, it's not "burned" and not blowing smoke from the exhaust...it's getting sucked out in vapor form through the PCV. The oil is going into the injection plenum and being burned off moderately.

It's like a $4 part, available at any autp parts stores..
Because of this belief (not confirmed, but many think it's true), many of us replace our PCV valve every other oil change. I actually do it every time, since I think it might be cheap insurance.

Yet some owners have never changed their PCV after thousands and thousands of miles with no problems.:_confused
My '01 with 77k doesn't consume a drop until I hit the highway for about 8 hrs straight.


You can change it yourself, super easy...
Here's a "How-To" I did:
http://www.vehicross.info/forums/showpost.php?p=247257&postcount=13



THE OEM PCV IS THE RUST COLOR THING, RIGHT ABOVE CYLINDER #3 ON THE DRIVER'S SIDE. CAN SEE IT AFTER YOU REMOVE THE PLASTIC ENGINE COVER.
IF YOU HAVE A RUST COLORED ONE, IT'S "LIKELY" THE ORIGINAL ONE INSTALLED AT THE FACTORY.
http://www.vehicross.info/gallery/data/500/849pcv.jpg

[Gussie2000]

It's very important to make note that ONLY the long block from the axiom's engine with the 8th digit of the vin number being a " X " is suitable as a donor for the VX.

The reason the short block can't be use is because of the axiom being equipped with a electronic throttle and therefor and different ECU.

[H3_VX]

That's a real common scenario in many of these failures. Many believe when there's no dripping, and no burning (smoke out the tailpipe) , that it's often related to the PCV valve. PCV =Positive Crankcase Ventilation, it's part of the emissions control system, but if it gets stuck (open IIRC), it allows the oil to be kind of sucked out.

When the oil is lost through the PCV valve, it's not "burned" and not blowing smoke from the exhaust...it's getting sucked out in vapor form through the PCV. The oil is going into the injection plenum and being burned off moderately.

It's like a $4 part, available at any autp parts stores..
Because of this belief (not confirmed, but many think it's true), many of us replace our PCV valve every other oil change. I actually do it every time, since I think it might be cheap insurance.

Yet some owners have never changed their PCV after thousands and thousands of miles with no problems.:_confused
My '01 with 77k doesn't consume a drop until I hit the highway for about 8 hrs straight.


You can change it yourself, super easy...
Here's a "How-To" I did:
http://www.vehicross.info/forums/showpost.php?p=247257&postcount=13



THE OEM PCV IS THE RUST COLOR THING, RIGHT ABOVE CYLINDER #3 ON THE DRIVER'S SIDE. CAN SEE IT AFTER YOU REMOVE THE PLASTIC ENGINE COVER.
IF YOU HAVE A RUST COLORED ONE, IT'S "LIKELY" THE ORIGINAL ONE INSTALLED AT THE FACTORY.
http://www.vehicross.info/gallery/data/500/849pcv.jpg

If a person has had NO oil usage in 80,000 miles should one still change the pcv?

[atilla_the_fun]

If a person has had NO oil usage in 80,000 miles should one still change the pcv?


The PCV is something that is periodically changed, it isn't meant to last forever on any vehicle. Take yours out, and rattle it around. There is a little ball on a spring inside. If you can hear the sound, it is still OK - if not then you should replace it.

[vt_maverick]

The Isuzu Axiom engine (from '04-?) is supposed to be an easy replacement and does not have the oil consumption issue that many of ours did/do. I can recall one guy did the swap (iamironman).

Axioms were manufactured from 02-04, with the 04 model year having a direct injection engine that was never available before or after that year in any other Isuzu vehicle. I believe this may be the engine that Gussie mentions above, because it is NOT compatible with the VX due to the injection/ECU difference. As for oil consumption, my 04 Axiom burns oil WORSE than the VX.

IMHO the Isuzu 3.5 is flawed in all models and all years. It appears to be less so in late 00-01 VX's and perhaps 02-03 Axiom's, but that's not really been proven. I'd try to find a 3.5 out of a 01-02 Trooper as a direct replacement if it were me - there should be tons of those out there in junkyards.