Acceleration problem

[specelec]

Started having problems accelerating. I can push gas pedal to a certain point, but if I push it any farther ( floor it ), it is like I just completely let off the gas. Sometimes if I hold it between the good and bad points, it will shudder.

I do have a MIL and will get the codes this weekend and post.

Has been happening for about a month ( multiple tanks of gas ).

Seems to be worse the colder it is. ( currently around 20 degrees F )
In park revving sounds OK until I try to go full throttle.
Any ideas??

My thoughts (please feel free to shoot down )

clogged catalytic converter??? (still original )

Help, if I keep getting on to the freeway at 40MPH, I am going to end up getting killed.

[Mr_Roboto]

It could be a converter, a cheap and easy thing I would check would be the fuel filter however. If you havn't changed it it probably needs it anyways tbh. Besides that, you may have a weakening fuel pump. Do you have any rotten egg smell from the exhaust? What about a rattling sound? You may try to go out for a little bit and see if the cat glows, if it does it's probably bad. That being said, don't only figure out if the cat is bad but rather WHY it's bad. They tend to have a long life if not drenched in fuel or the likes.

[specelec]

Funny you should mention fuel filter. I am currently on the 2nd fuel filter, and tried to change it last fall, but after working on it for about an hour and a half of soaking it in PB Blaster, and wrenchin it back an forth, one of the lines started to kink, and I proceeded to tighten it back up and returned the filter.

Has anyone recovered (easily) from a broken line at the filter?

I was thinking of cutting the line, buying 2 short pieces of metal fuel line to screw into filter, and 2 short pieces of rubber fuel line and clamps to reconnect the hard line to the rubber line.

Or I could take it and have it done?!?!?!

I will check for rattles, glowing and rotten egg smell.

Gotta find my autoenginuty cable to pull codes.

[LiftedAWDAstro]

First things first...get the SES code. Then we go from there.

[specelec]

Ok, I have pulled the codes and attached a screen shot of them.

Today is a little warmer ( ~32 ) and it is running a little bit better...strange!

More info: I have replaced the dist cap and rotor within the last month (arcing). Replaced w/ AC Delco.
O2 sensors (3) were replace last summer. Bosch

Keep the input coming, I want to fix this soon.

Thanks.

[specelec]

Another update.

Yesterday was ~45 degrees F and it ran even better, still hesitation at full throttle, but was much peppier, and had more throttle range before it starting bogging.

Must be the whole running lean situation.

Any thoughts on where to start?

Thanks Again.

[specelec]

Ok, you guys are the pros.......No ideas???

There has got to be someone who has seen this issue.

Thanks.

[Jboy2]

This is kinda what happened to my buddies Safari. I told him to clean the Oxygen sensor to see if it made any difference and he sayed it solved the problem.

Hope that helps

[sfeaver]

The 131 and 151 codes deal with the heater circuit in the oxygen sensors. P0420 is either your cat is bad, or the sensor behind the cat is bad. Most likely the cat.

One thing you could try is to disconnect the sensors in question and see if the drivability improves. A bad sensor could lean out the motor. Staying lean for more than 50 seconds will set this code. Things to check are power feeds and grounds to the heater part of the sensor.

I've had nothing but trouble with Bosch stuff by the way.

Scott

[LiftedAWDAstro]

The P0420 code in my 98 was the cat. converter. I also had poor acceleration. Put a new converter in and the code went away.

[specelec]

Thanks for the update. I want to put some time into the van this weekend. It's my M-F vehicle ( NO WORK, NO PAY )

I will check the O2 sensor behind the cat, and start looking into a cat replacement.

Any tips / suggestions on type of cat or installation?

Auto Zone has a universal cat. Is this just a cut the old one out, and slip over / clamp?

I dont really want to fight with the bolts at the exhaust manifold.

Thanks again to all who have helped!!!!

[astrozam]

Thanks for the update. I want to put some time into the van this weekend. It's my M-F vehicle ( NO WORK, NO PAY )

I will check the O2 sensor behind the cat, and start looking into a cat replacement.

Any tips / suggestions on type of cat or installation?

Auto Zone has a universal cat. Is this just a cut the old one out, and slip over / clamp?

I dont really want to fight with the bolts at the exhaust manifold.

Thanks again to all who have helped!!!!

I believe the universal cats are cut out weld in.

[LiftedAWDAstro]

I bought my replacement 3" in/out cat on Ebay and took it to a local shop where they welded it in for $50 labor. Well worth the money due to the tight space to work in.

[specelec]

FINAL RESOLUTION

With the cat and the fuel filter replaced this thing runs like new.

No more staring at the SES light.

Its almost like having a new piece.........

Thanks to everyone for your input!

[astrozam]

Good to hear,and thanks for letting us know how it turned out.