running rich?? no codes?? cats getting red red hot??

[1998Explodasport]

Also I forgot to add that when it sputters and is about to stall it backfires too.

I don't have much history on this truck, I just bought it. It's a 2001 SOHC 2 door Sport. I just replaced the plugs with Iridium plugs, swapped MAF with a known working MAF, new air filter, fuel filter etc. Fuel pressure is at about 60psi, I thought it was high until I checked and I guess it's normal. After running the truck for 5-10 mins. it will lose alot of power and if I press the gas it will eventually stall. I looked under the truck and I noticed the cats were glowing red. If I shut the truck off for a few minutes and start it back up it will run fine for a few minutes and then do the same.

Just want to add that there is no codes at all, no pending or trouble codes.

 

[1998Explodasport]

After a search it seems that my FPR is bad. If it was bad would it still read that I am getting the correct fuel pressure and also wouldn't it cause a CEL??

 

[Xplorer82]

I looked under the truck and I noticed the cats were glowing red. .

you need to change your cats. they are not supposed to "glow red". i would start there. that was the problem with my camaro and loss of power, as well as my explorer started doing the same thing...

good thing is, you will get a $100 cash back when you scrap the old cats . i paid all of $195 for my direct fit magnaflow cats after i scraped my old ones in ($295 shipped minus the $100).

Edit.... you can try the FPR, but my focus would be on the cats. that is your call, i know money does not grow on trees but cats get my first bet. just not sure why that have not thrown any codes

 

[1998Explodasport]

you need to change your cats. they are not supposed to "glow red". i would start there. that was the problem with my camaro and loss of power, as well as my explorer started doing the same thing...

good thing is, you will get a $100 cash back when you scrap the old cats . i paid all of $195 for my direct fit magnaflow cats after i scraped my old ones in ($295 shipped minus the $100).

I was going to replace the cats but wouldn't I have no power all the time if they were bad? At first start up it runs fine until it's warmed up then it starts losing power. I can shut it off for a few moments and it will run fine for a minute until it loses power again. If am running rich and I replace the cats I will ruin the new cats.

 

[Xplorer82]

I was going to replace the cats but wouldn't I have no power all the time if they were bad? At first start up it runs fine until it's warmed up then it starts losing power. I can shut it off for a few moments and it will run fine for a minute until it loses power again. If am running rich and I replace the cats I will ruin the new cats.

that is true on running rich, but if you planned on replacing them then add that to the list(and hold off as long as possible till you find the running rich problem) and focus on that running rich.

and no, it wouldnt mean (in all cases) that you would all the time have no power, like i stated, i had the same problems with my camaro (real bad) and started to get more loss of power over time till i finally swapped the cats on my explorer. gained all my power back as soon as both vehicles cats were replaced. it all depends on how bad they are clogged as well.

 

[waskly]

I was going to replace the cats but wouldn't I have no power all the time if they were bad? At first start up it runs fine until it's warmed up then it starts losing power. I can shut it off for a few moments and it will run fine for a minute until it loses power again. If am running rich and I replace the cats I will ruin the new cats.

first start up the car is not controlled by the pcm till it hit pcm control (engine temp at operation temperature), the vehicle runs rich, which is why you are not noticing lack of power, till the pcm starts controlling the air / fuel mixture and makes it proper that you notice the lose of power.

 

[1998Explodasport]

first start up the car is not controlled by the pcm till it hit pcm control (engine temp at operation temperature), the vehicle runs rich, which is why you are not noticing lack of power, till the pcm starts controlling the air / fuel mixture and makes it proper that you notice the lose of power.

This I didn't know but you haven't given me any direction to go in. Are you suggestion I replace the cats? I'm not rich but money isn't an issue I just want to spend it as wisely as possible.

 

[1998Explodasport]

Also wanted to add that when it sputters and is about to stall it will backfire.

 

[waskly]

This I didn't know but you haven't given me any direction to go in. Are you suggestion I replace the cats? I'm not rich but money isn't an issue I just want to spend it as wisely as possible.

yes if the cats are turning red, they are bad, most likely restricted. easy way to tell is test back pressure or drop the cats down and see how the truck runs. but if they are turning red, the cats are clogged.

 

[1998Explodasport]

Well tomorrow I am going to start throwing parts at it, I guess I will start with new wires and a spare coil I have then I am going to replace the FPR and if that doesn't work I guess I have no choice but to replace all the cats. I am going to see if the exhaust place will remove the cats and let me run the truck for a bit to see if that clears up the problem.

I have been searching this all night and even though I think the cats are bad I have to make sure it's not running rich first so I don't kill the new cats.

 

[my98nnj]

If it was running too rich all the time it would throw an O2 error code for the rich condition.

 

[slo5oh]

I'd start by reading your plugs.
link

Something else that can cause your exhaust to overheat fast is when your timing is either to low or your computer controlled advance is not working. I had a smog tech forget to put my spout plug back in on my mustang and about 60 seconds into the 2k rpm test my headers were glowing.
Just something else to look at.

 

[budwich]

I don't believe your truck has an FPR... it uses a "lossless return" system (ie. no return), the fuel pump is computer controlled to "regulate" pressures... I think. Anyways, the "glow" doesn't sound good. As suggested, you might want to drop your cats... possibly just run a "temporary" straight pipe "intermediate". That way you can test "theories" on what is happening to your power. IF it comes back, then you can focus on your cats BUT there is likely a reason for your bad cats that you will need to solve otherwise, you are likely to ruin new ones.

 

[waskly]

Well tomorrow I am going to start throwing parts at it, I guess I will start with new wires and a spare coil I have then I am going to replace the FPR and if that doesn't work I guess I have no choice but to replace all the cats. I am going to see if the exhaust place will remove the cats and let me run the truck for a bit to see if that clears up the problem.

I have been searching this all night and even though I think the cats are bad I have to make sure it's not running rich first so I don't kill the new cats.

if the bolts are not rusted round, you could probably remove the 2 bolts at each manifold to exhaust pipes on each side and let them hang on the hangers and do this yourself.

 

[1998Explodasport]

Well I am an idiot. lol. The problem was a bad fuel pump. I did check the fuel pressure a few times and it always read above 60psi so I would unhook it and figured it was good. Last week I lent a friend my fuel pressure gauge and I just got it back so I go to my garage and hook it up and it's above 60psi. I drive around the lot for a few minutes and it starts bogging so I check the pressure and it's down to 20psi and dropping. I replaced the fuel pump today and so far so good I am glad I didn't kill the cats there seems to be alot of pressure coming out the pipes and they are not turning red anymore.

I always knew a lean mixture would turn the cats red I just thought I was getting good pressure. I appreciate everyones help in this thread.

 

[Xplorer82]

I appreciate everyones help in this thread.

if i was any help at all, ur welcome.

glad you got her running good now. keep a eye on those cats though.