2001 bonneville 3.8.

quit running on highway while trying to pass. barely will start now, cranks and stops cranking at some points of revolution. (not hydro-lock) if it starts, sounds terrible, shakes, rattles will barely idle. terrible smell from exhaust if it starts. put in gear and it stalls.

seems like ignition timing waaaay off? almost seems like older distributor ignition cars with timing advanced way too far? cranks nice and smooth with plug wires off.

could it be valve timing? timing gear jumped tooth?

Do you have acess to a code reader to see what the stored codes are?

What does the oil look like, how old is the battery and what voltage is the battery at?

cant get car to autozone to check codes, but check engine light came on after the highway event. everything else fine, was running perfect before. oil good, no antifreeze in oil, plugs look good. battery new, cranks awesome with wires off. plug wires on causes it to barley crank, even sounds like its freezing up at some spots of revolution with wires on.

thinking plugs are firing at wrong time. does cps control spark timing?

Yes the CPS sends signals to control ignition. It would help a lot to see what codes are present. Sometimes you can rent or borrow a code reader. You night try calling AZ and see if they can do that. Without seeing the codes, you could end up throwing a lot of money t it and not fix it.

rented obd2. only code PO300. randon/multiple cylinder misfire.
that code doesn't help much, I already knew that!

whatever happened to cause this problem was caused by high rpm's after downshift while passing a car on highway. not sure if rpm's would break a sensor.

any ideas on what to troubleshoot without replacing a whole bunch of expensive, non-returnable sensors????
THANKS FOR ANY IDEAS ANYONE MAY HAVE ON WHERE TO START!!!!!!!!!!

TRIPLE check plug wire order... even if you have already. Its the #1 cause of this.

_________________
Andrew - owner/operator of Bonnevilles Unlimited

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 55k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 95k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 260k | Official Bonneville Hauler

had 2 & 4 switched. had even labeled them. thanks...thought I was a good mechanic.

Anyway, back to problem... runs choppy, but no vacuum leaks (sprayed starting fluid all around, no change in idle), sounds like a dry grinding noise coming from crank around balancer. not an accessory making noise, took serp belt off to see if that was. no knocking sound but after 5 minutes of running, gets a faint knocking sound. Initially thought a spun rod bearing, but wierd smell from exhaust after highway incident. rod bearing couldnt cause that. oil pressure drops from 40 cold to about 20 hot. high friction somewhere because when shut key off, engine stops immediately. antifreeze full, has never lost a drop, so I rule out intake problems.

I'm lost.

So it runs a LOT better after the plug wires are correct, but still a little choppy huh?

Could you post a video?

Knocking and 20psi oil pressure when hot are not good signs.

_________________
Andrew - owner/operator of Bonnevilles Unlimited

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 55k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 95k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 260k | Official Bonneville Hauler