Idles fine, falls on her face when pushed

[v8famvan]

I would recommend using a simple vacuum gauge to see what is happening.

What a properly flowing engine should do is have a slight drop when the throttle is opened slowly and then increase in vacuum as the revs are brought up.
If the vacuum continues to drop as the revs are brought up, I would suspect a plugged exhaust.

[fasteddy]

Thank you, sir. I had forgotten that one. As best I remember, the map pressure increased as the throttle was opened slowly, then dropped as the rpms came up to match the throttle opening, but I'll check it again. That should mirror the vac gauge action unless I've screwed the pooch with the logic. I don't have a real vac gauge handy, just the one on a hand vac pump, but they are cheap. Nobody teaches vac gauge diagnosing any more, do they? Useful tool.

With your experience, do you have any other suggestions? Is it possible to have a bad crank angle offset in the pcm rom setup, or do you think mechanical is the problem? Could somebody have been fooling with the PROM burn, or does thing even have an eeprom?

It will go on a real big boy analyzer Tue, and we'll see what that shows, but I'm losing faith in 'lectrons...

[fasteddy]

Don't you hate the poster who blows in and gets you to diagnose a real puzzler of a problem, relying on reported data from somebody who doesn't know the van, and you never know if he fixed it or not, or get a word of thanks....

This is another one of those.

Jest teasin'. I'm not that guy.

v8famvan hit it out of the park. pulled ohtwo and it ran better. Off to find the best hiflo cat that fits.

Thanks, all...

BTW, this is an exception to the rule that 90% of all car problems are electrical...

[1Gary]

To remove the O2 sensor and then drive it to find it runs normal would tell you the cat is bad.

[fasteddy]

I agree. You from Kodak Town? I have inlaws there. Know any Berwinds? Pretty town you got there, even for a son of the Confederacy, but y'all talk real funny...

[1Gary]

Nope-From Florida.

[fasteddy]

Test pipe installed, runs like a champ, nice little muted growl when you punch it. That main muffler is a beast, huge. I keep thinking Magnaflow when I do the 3" all the way back from the td17c, IF I can find some oem syty exhaust manifolds and crossover for less than my firstborn. I'd settle for just the cast iron. I can fab the rest.

It also blew the fuse AGAIN that's marked aux, #7, the 25a, that powers the aldl connector and the aux power outlets pside footwell and rear dside, and dunno what else. Put a new 25a in there and it's holding so far, but I haven't plugged a load into the outlets again. Had a radioshack 300w inverter and a phone charger in there before, neither loaded.