1998 Mustang GT Problem Can Anyone Help

[Get E Up 98]

1998 Mustang GT Problem #2

This is what happened..driving down the hwy. Check Engine Light starts flashing. I start to notice my car is hesitating. It has no pickup...when im sitting still and idling i feel like im in a jet. When i get up to speed i can still feel it hesitating. As I get close to home I lose almost all power that I have. I have no pickup and I hear a whislting coming from underneath the engine. I pull over and notice the hose that goes into the DPFE pooped off...I look under the car and the cat converter closest to the header and it is cherry red and glowing. I shut off the car and look under the hood. I notice that both outlets the run off the DPFE sensor melted off. I also noticed that it blew a hole in the hose that runs to the DPFE sensor. So I know I need a new hose. Cause everytime I start the car and give it some gas it blows the hose off that runs to that DPFE sensor and exahust fumes come puring outta that hose under the hood. What should i do from here....If anyone could give me some advice I would appreciate it..I'd like to go rescue my car from the muffler shop if I can... =p

 

[Red mustang Gt 46]

Sounds like a clogged - worn out convertor. Good excuse to replace it with a high flow X or H catted pipe..

 

[tjm73]

Sounds like a clogged - worn out convertor. Good excuse to replace it with a high flow X or H catted pipe..

YUP!!! What he said...plugged up catalytic converter. I reccomend an X-pipe with cats as a replacement.

 

[GDawg]

I melted some cats on an old T-Bird I used to own... Did the same thing as you described. Supposedly it happened because my fuel filter was clogged and I was running way too lean. At least that's what the mechanic said.

I hope you don't live in California...

 

[stang9gt]

When the light flashes, it means something is wrong that could cause catostrophic damage to the cats...

 

[chevyboy_z28]

a catalytic convertor usually will not go bad on its own tho. they fail b/c of some other problem with the car. so replacing the cat/h-pipe with an aftermarket unit will not completely solve the problem, it could be anything from a fuel filter like the guy before me said, to oil fouled plugs, etc. once you fix the original problem u could use this as an excuse to get a high flow/off-road h or x pipe tho?

 

[mrvax]

a catalytic convertor usually will not go bad on its own tho. they fail b/c of some other problem with the car. so replacing the cat/h-pipe with an aftermarket unit will not completely solve the problem...

The Chevy guy is right. Are you a GM certified mechanic? Good job.
Yup, something is already wrong and it destoryed the cat. Have you ever changed the fuel filter? Don't start swapping crap out at random; get a new catalyic converter but only install it after you have resolved the problem. This probably needs a "real" mechanic to diagnose.

 

[70stangcoupe]

As recommended, take it to a qualified professional.

After that, install an Off Road midpipe.

 

[Get E Up 98]

OK guys I got one for ya...The cat. converter was pressure tested today and was perfectly fine. So now what? I am going to be taking it to a ford dealer tomorrow to get a diagnostic test done on it...I was told I have 6 cats on my car by a muffler mechanic...is that true and it would cost $1200 to replace them cause its all one assembly. We bypassed the EVR valve Vacuum Regulator and revved the engine to 5000 RPM's and the hoses held up and didnt pop off....Now I was told less vacuum = more fuel to compensate which could have caused the cats to run hotter..maybe dumped to much fuel and caused the cat to run hotter burn hotter....so what do ya'll experts think??

 

[chevyboy_z28]

...I was told I have 6 cats on my car by a muffler mechanic...

not quite, theres 4 convertors and two resonators. although the resonators arent as restrictive as the thick honeycomb designed catalytic convertors, they too hamper the exhaust note but dont get clogged like cats do so they dont pose a problem. as stated before an offroad x or h midpipe will eliminate all that junk and help your car breathe enhancing overall performance, but you gotta get the main problem tackled first.

back to the main problem; as for the cat being tested and checking out ok, ide say that you got lucky. see the only assumption i can make is that when your egr (exhaust gas recirculation) hose blew off it created a rich condition b/c those exhaust fumes were no longer being pulled back into the intake and reburned, instead they flowed down thru the manifolds and thru the cat. i bet it was the left cat that was glowing, b/c that the side that the egr hook up is on. i believe the hesitation came from the computer sensing this rich condition from the O2 sensors and pulling spark/retarding the timing (hence the car running like crap). i say your lucky b/c the cat would only survive for so long with a rich condition like i assume you have until it clogged up. this is all off the top of my head and happens to be the best conclusion i can come up with... and no im not a GM certified mechanic, but i did stay at a Holiday Inn express last night !...let me know how things work out, im interested to know.

 

[Get E Up 98]

So what do you think may be the problem....maybea vacuum problem within the EVR sensor or something....iif i bypass it it seems to run ok..a little crappy but when i give it gas it doesnt pop the hoses off. Although im sure I'll find out tomorrow whats really wrong with it just wanted to see if yall could figure it out with the sypnosis I have given you..its a tough one...and has even baffled some pretty reliable mechanics....only the diaognostic test will tell....

 

[GDawg]

$12.00... have you replaced your fuel filter...? it's a cheap fix so if it's not that, what have you lost but a couple bucks. How many miles do you have on your car? Has the filter ever been replaced?

 

[LordWilmar]

I had the same issue, minus the hot cat, it turned out to be my fuel pump was pushing out 24psi instead of 35-40. I just ordered the new pump, I'll let you know if it works

JDW