Water our worst enemy.

[tom4bren]

Now, since I went into deep water and I am 100% sure the exhaust was underwater is there any chance that water could have ran all the way to the cat converter?
What other things could have blocked my cat?
Mechanic says after letting the VX running and not moving, catalityc converter starts glowing red of how hot it gets. I still have to see it in person.

Not likely that water backed up into your cat unless you turned off the engine whilst it was under water. The exhaust pressure would have kept it from flowing that far up the system. If you turned your engine off, then absolutely it could have.

Yes, the cat can get cherry red ... but it usually doesn't. Even if it's not cherry red, it's still HOT!!!!. That's one of the issues with 'swimming' any cat equipped vehicle. Hitting the cold water with a hot cat can cause some really wonky things to happen. Metal just doesn't like to be cooled that rapidly.

IIRC, the way a cat works is that it contains rare metals (platinum I think) that react with the exhaust gasses. The chemical reaction causes the heat that is used to burn up any unspent fuel and other nasty stuff that isn't supposed to be in our atmosphere. Hence the name catalytic converter ... or catalyst. Believe it or not, the cat is actually sacraficial in that regard. It will eventually use itself up. They are designed however to not get used up for a long, long time (hopefully the life of the vehicle).

[subject47]

I have had my vx swimming with water 6 inches up the windshield. I have a snorkel so it can still breath never had any issues with idle and random acceleration. I however have sealed my fuse box intake coil packs pretty much anything Electrical I could think of.

However any leak in the exhaust while under water can allow water to back up from the tail pipe because the pressure escapes through the leak. It only takes a small amount of water to shatter a nice hot converter the are porcelain after all and yes they do have platinum in them. Water up the tail pipe is a ricer trick to de cat a car. Couple of things about a clogged/shattered cat if its shattered you should be able to shake it and hear it rattle unless it all fell out. A clogged cat can leave the exhaust smelling like rotten eggs.

A red hot cat can also indicates you could be running very rich. Since the extra heat in a cat is caused by the chemical reaction burning the fuel. Have you checked to see if you have water in your spark plug wells

[Pepino]

Not likely that water backed up into your cat unless you turned off the engine whilst it was under water. The exhaust pressure would have kept it from flowing that far up the system. If you turned your engine off, then absolutely it could have.

oops.. I did turn it off while underwater.

However any leak in the exhaust while under water can allow water to back up from the tail pipe because the pressure escapes through the leak. It only takes a small amount of water to shatter a nice hot converter the are porcelain after all and yes they do have platinum in them. Water up the tail pipe is a ricer trick to de cat a car. Couple of things about a clogged/shattered cat if its shattered you should be able to shake it and hear it rattle unless it all fell out. A clogged cat can leave the exhaust smelling like rotten eggs.

Yes maybe I also had a leak, first offroad trip, broke the exhaust system, had it welded back but it might not have been a perfect seal. Yes the mechanic said something about all the porcelain being broken or gone or something like that. Will look for an after market cat, or maybe go decat. Maybe Ill get a couple horsepower.

Thank you guys, will keep you informed.

[tom4bren]

yah. Unless you are in a real bad stuck ... & will be for more than 30 minutes, you're probably better off leaving it running.

I just went back and re-read your original post & I hafta agree. Sounds like a clogged cat.

[Marlin]

That is actually good news, easy to fix, no electrical gremlins to spend months chasing. Good luck! As for decat,be careful, it is illegal

[Pepino]

That is actually good news, easy to fix, no electrical gremlins to spend months chasing. Good luck! As for decat,be careful, it is illegal

I´m not to worried about the legal consecuences, I am more worried about th ecological consecuences but I mean since I am already getting 10mpg I feel like I am driving a Ferrari at full speed all the time and burning and burning gas all the time. My Focus RS is decat too.
http://www.youtube.com/watch?v=sJugNII9ktg

This same exhaust

[Pepino]

If I go de-cat will I get a Code sent out? Check Engine light?

[Pepino]

Got back my VX from the mechanic today. Went the de-cat way for now, no code was thrown, cleaned MAF sensor and everything. Mechanic tested it with no problem.
Took it back home and everything was fine, then all the problems came back. Managed to get a video. Check engine light came on went to check it and it says o2sensor.

I am not sure if there is a way to embed a video into the post, Ill leave the link if anyone can help me out.
http://www.youtube.com/watch?v=gdebm...ature=youtu.be

This is what happens while I am accelerating, it has also happened while at a complete stop only difference is that engine RPMs decrease slowly until it dies, I start it up and everything is fine.

[subject47]

Could be three things, bad news is that the three things are important, Air, Fuel, or spark.

ok how long did it take for the problem to start. this is important, while the engine is cold it runs a preprogrammed fuel map... it runs rich (good thing). once it warms up it starts to take readings of the fuel air mixture using the o2 sensors, then adjusts for the correct afm.

if it warmed up and came off the fuel map and tried to put the correct fuel in but could not it can run like this.

did you notice black smoke out the back?

the same goes for ignition timing, if the timing is off i.e. bad crank sensor the truck can run like ***, I get the same thing on my 89 bmw if the crank position sensor gets wet. runs just like that backfires dies and takes for ever to restart.

the air intake can also be premmaped untill the engine warms.

the two differrent modes are called closed/open loop, i forget which is which atm.

since you have cleaned the MAF and i assume have no air blockage since it was running, I think we can out the Air problem to the side for now.

I would start with the spark side first, checking over the whole system overview style, looking for bad conections, lingering water then do the same with fuel.

drive the truck till warm see if it happens again.

If it does, check the entire ignition system, pull off each coil one at a time look for water pull each plug look for cracked ceramic on the plugs, look at each plug they should be dry, kinda brown/metal color with minimal soot, carbon build up. if you find one that is not you may have found a symptom of your problem. soot is caused by too much fuel not burning correctly.

I really want to say its a problem with timing on the ignition side. I would say the crank sensor appears to be working.

How deep was the water inside the truck? the ecu is only inches above the tranny tunnel

[Pepino]

Could be three things, bad news is that the three things are important, Air, Fuel, or spark.

ok how long did it take for the problem to start. this is important, while the engine is cold it runs a preprogrammed fuel map... it runs rich (good thing). once it warms up it starts to take readings of the fuel air mixture using the o2 sensors, then adjusts for the correct afm.

if it warmed up and came off the fuel map and tried to put the correct fuel in but could not it can run like this.

did you notice black smoke out the back?

the same goes for ignition timing, if the timing is off i.e. bad crank sensor the truck can run like ***, I get the same thing on my 89 bmw if the crank position sensor gets wet. runs just like that backfires dies and takes for ever to restart.

the air intake can also be premmaped untill the engine warms.

the two differrent modes are called closed/open loop, i forget which is which atm.

since you have cleaned the MAF and i assume have no air blockage since it was running, I think we can out the Air problem to the side for now.

I would start with the spark side first, checking over the whole system overview style, looking for bad conections, lingering water then do the same with fuel.

drive the truck till warm see if it happens again.

If it does, check the entire ignition system, pull off each coil one at a time look for water pull each plug look for cracked ceramic on the plugs, look at each plug they should be dry, kinda brown/metal color with minimal soot, carbon build up. if you find one that is not you may have found a symptom of your problem. soot is caused by too much fuel not burning correctly.

I really want to say its a problem with timing on the ignition side. I would say the crank sensor appears to be working.

How deep was the water inside the truck? the ecu is only inches above the tranny tunnel

No black smoke, problem happens randomly but never when engine is cold, I might have driven for 30 minutes when it starts, sometimes it takes more than an hour drive, if it dies I turn the ignition on and starts inmediatly like nothing is wrong.

Ignition seems to be fine, did a whole tune up and changed sparkplugs and they were fine.
No blockage in the intake, maf cleaned, I am even running right now without the cone filter. While I get a new better one, problem seemed to stop everytime I took the air filter out, but after a week of driving like that problem came back. So I thought it had something to do with intake and air.

I am still trying to figure out whats going on, doesnt seem to be a big deal If I dont push the engine to far. I am still trying different things to see what fixes the problem.

Thanks for all the input, I will let you know when the problem gets fixed, if it ever gets fixed.

[subject47]

hmm I was pretty drunk that night, I dont even remember typing that. lol