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Problems after Seafoam... Help?!

C

collkid

NAXJA Forum User
Location
Highlands Ranch, Colorado
This is on my sisters Jeep. 1990 (renix) with 192,221k miles. 4.0, AW4, NP231.

It has always Idled a little lower then My XJ (2000) but I figured it was kind of normal (lower as in 650-700 RPM) I did a full tune up and figured i might as well throw in some SeaFoam to give it a nice cleaning. I checked and re-checked to make sure that I got everything back to normal (wires going to the right plugs).

Well now, It misses, smells terribly of Gas, can't get over 2k RPM and will die from Idling so low.

I'll probably replace the O2 today (probably needs to be done anyway)

But any other ideas?

Thanks,
Jeremy
 
I replaced them, along with the Cap, Rotor, and plugs themselves. For a few days it was running (just hard idle but she was going 75 without problems) so it has gotten worse to the point where it doesn't start. Could a bad O2 Cause a No start?
 
No, bad o2 usually won't cause a no start. It will just run off the MAP and calculations. Might run like dirt, but it would just stay in open loop.

Same thing with TPS, usually doesn't cause a no start. BUT if your TPS is shorted to WOT, it may be stuck in clear flood mode and you'll never get it started. I'm just speculating here, don't even know if the renix has clear flood.
 
DanMan2k06 said:
No, bad o2 usually won't cause a no start. It will just run off the MAP and calculations. Might run like dirt, but it would just stay in open loop.

Same thing with TPS, usually doesn't cause a no start. BUT if your TPS is shorted to WOT, it may be stuck in clear flood mode and you'll never get it started. I'm just speculating here, don't even know if the renix has clear flood.
Click to expand...

What about the IAC, think that would cause a no start?
 
This is a common problem with pouring Seafoam down the throttle body or in the power brake hose. It is just too much of a good thing and takes out the O2 sensor. You don't need to make "white smoke". Just pour the bottle in a 1/4 tank of gas and drive. No drama. When it is done, you will have a clean engine. I did this and verified it by a tear down and it works. This if the fourth time I have seen this come up on forums. But people just insist on pouring it down an intake. The other way is much simpler and in the long run cheaper.
 
I think you smoked your O2 sensor -- next time you do sea-foam pull the vaccum hose from the brake booster and suck a 1/2 bottle directly into the intake through that hose, instead of pouring in the throttle body.
 
I'm going to kinda agree with xj-grin but I'm thinking the issue may be with the catalytic converter.

Seafoam helps to clean carbon deposits and other gunk from the engine. That carbon and gunk doesn't magically disappear. Some might get burned during combustion, but generally, it all just becomes carbon.

The inside of your cat converter is comprised of thousands of small screens coated in catalyst metals. That screen is pretty small, not unlike the radiator core in our XJ's. Debris will clog them up.

If you were blasting a bunch of carbon into the cat, along with steam, you're creating a very large potential cat destroyer. If the cat gets humid inside, then you throw a bunch of dirt at it, it's gonna clog.

There's TONS of google info containing threads on automobile enthusiast sites where folks claim Seafoam killed their catalytic converter, and others that swear by it and support it's claims that Seafoam is catalytic converter safe.

True, Seafoam itself doesn't have ingredients that would clog or breakdown a cat converter, but again, it cleans crap outta the engine that certainly could clog an already carbon fouled cat......

Suggestion:

First, when you crank the engine and it won't start, you're smelling alot of fuel right? Pull the plugs and see if they're getting fuel fouled - wet, gassy smelling. I'm gonna guess that they will be.....

Next, pull the fuel pump relay to ensure no fuel is being supplied. Pull the plugs, let the cylinders dry out and set the plugs in the sun, or clean with brake cleaner. Give the engine about 30 minutes with the plugs out, then replace. Crank the engine over several times.

Get a buddy, and after you crank the engine over, have them listen to the throttle body opening (have the tube off for this) and see if you/they hear hissing air sound after it cranks. If you hear hissing, or can even feel a bit of air coming out of the throttle body, I'm gonna say your cat is completely clogged.

If no hissing air, replace the fuel pump relay and then see if it will start and run. If it starts, runs, but runs like crap, or even stalls out after a minute or two - or less, then I'm gonna say that the cat converter is clogged but not plugged and flowing like it should.

If you suspect after all those processes that your cat may be clogged or plugged, unbolt it from the exhaust to create a decent gap, or let it hang down completely. Then see if it starts and runs. If it runs, the cat is the problem.
 
YELLAHEEP said:
I'm going to kinda agree with xj-grin but I'm thinking the issue may be with the catalytic converter.

Seafoam helps to clean carbon deposits and other gunk from the engine. That carbon and gunk doesn't magically disappear. Some might get burned during combustion, but generally, it all just becomes carbon.

The inside of your cat converter is comprised of thousands of small screens coated in catalyst metals. That screen is pretty small, not unlike the radiator core in our XJ's. Debris will clog them up.

If you were blasting a bunch of carbon into the cat, along with steam, you're creating a very large potential cat destroyer. If the cat gets humid inside, then you throw a bunch of dirt at it, it's gonna clog.

There's TONS of google info containing threads on automobile enthusiast sites where folks claim Seafoam killed their catalytic converter, and others that swear by it and support it's claims that Seafoam is catalytic converter safe.

True, Seafoam itself doesn't have ingredients that would clog or breakdown a cat converter, but again, it cleans crap outta the engine that certainly could clog an already carbon fouled cat......

Suggestion:

First, when you crank the engine and it won't start, you're smelling alot of fuel right? Pull the plugs and see if they're getting fuel fouled - wet, gassy smelling. I'm gonna guess that they will be.....

Next, pull the fuel pump relay to ensure no fuel is being supplied. Pull the plugs, let the cylinders dry out and set the plugs in the sun, or clean with brake cleaner. Give the engine about 30 minutes with the plugs out, then replace. Crank the engine over several times.

Get a buddy, and after you crank the engine over, have them listen to the throttle body opening (have the tube off for this) and see if you/they hear hissing air sound after it cranks. If you hear hissing, or can even feel a bit of air coming out of the throttle body, I'm gonna say your cat is completely clogged.

If no hissing air, replace the fuel pump relay and then see if it will start and run. If it starts, runs, but runs like crap, or even stalls out after a minute or two - or less, then I'm gonna say that the cat converter is clogged but not plugged and flowing like it should.

If you suspect after all those processes that your cat may be clogged or plugged, unbolt it from the exhaust to create a decent gap, or let it hang down completely. Then see if it starts and runs. If it runs, the cat is the problem.
Click to expand...

Ah interesting, I do know that the cat is bad, it rattles when I hit it with a hammer, but I never thought that it would cause a no start issue.

Only problem I have is that the Exhaust is so rusted out, I can't just pull it apart, it'll need to be cut out. :(

The only thing I know, Gas (or some liquid) is coming out of the back of the exhaust, doesn't this mean its flowing ish? atleast enough?
 
collkid said:
Ah interesting, I do know that the cat is bad, it rattles when I hit it with a hammer, but I never thought that it would cause a no start issue.

Only problem I have is that the Exhaust is so rusted out, I can't just pull it apart, it'll need to be cut out. :(

The only thing I know, Gas (or some liquid) is coming out of the back of the exhaust, doesn't this mean its flowing ish? atleast enough?
Click to expand...

well the liquid should be water. I dont think hitting your cat with a hammer is a good indication if its ok or even a good idea. using seafoam would'nt PLUG your cat, maybe get it dirty or something, but it would have to be pretty bad to PLUG it. if it was an 02 it would start just run like crap and throw a check engine light. the part you cleaned with break cleaner should be the first thing you check.
 
YELLAHEEP said:
I'm going to kinda agree with xj-grin but I'm thinking the issue may be with the catalytic converter.

Seafoam helps to clean carbon deposits and other gunk from the engine. That carbon and gunk doesn't magically disappear. Some might get burned during combustion, but generally, it all just becomes carbon.

The inside of your cat converter is comprised of thousands of small screens coated in catalyst metals. That screen is pretty small, not unlike the radiator core in our XJ's. Debris will clog them up.

If you were blasting a bunch of carbon into the cat, along with steam, you're creating a very large potential cat destroyer. If the cat gets humid inside, then you throw a bunch of dirt at it, it's gonna clog.

There's TONS of google info containing threads on automobile enthusiast sites where folks claim Seafoam killed their catalytic converter, and others that swear by it and support it's claims that Seafoam is catalytic converter safe.

True, Seafoam itself doesn't have ingredients that would clog or breakdown a cat converter, but again, it cleans crap outta the engine that certainly could clog an already carbon fouled cat......
Click to expand...
X2

BAMF95 said:
well the liquid should be water. I dont think hitting your cat with a hammer is a good indication if its ok or even a good idea. using seafoam would'nt PLUG your cat, maybe get it dirty or something, but it would have to be pretty bad to PLUG it. if it was an 02 it would start just run like crap and throw a check engine light. the part you cleaned with break cleaner should be the first thing you check.
Click to expand...

Have you ever experianced it,I have on a girlfriends 96XJ.Put a brand new one on and it clogged back up within the month,had to find the real problem then!If a cat "rattles",its F***** up!
 
Renix= no CEL. go borrow a voltage meter and test the TPS. search to find the right way of doing it. look through the renix files or something like that. the cat would be a good starting point IMHO. then the IAC then the TPS if that doesnt work you might just be flooded out and have to pull plugs. the renix does have a clear flood mode just hold it wide open. post up your results. happy exploring! :repair:

EDIT: the first time i did the seafoam tune up i had to pull my battery terminals to "reset" something. it ran the whole time so might not be your prob. the old timers know more about the RENIX system than i do but its pretty simple. pull the MAP hose and blow it out also.
 
Last edited:
i run sea foam in all my rigs. 78 VW bus 88 XJ 95 Tahoe 96 GMC 1500 and my 99 XJ. i use the brake vacuum line and have never had a no start problem. seen it poured in an intake and it ruin the sensors. then things get strange. half a can in the tank and half in the intake ever 3000k works for me
 
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