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screwballl · 05-30-2005, 04:47 PM

ok i did some digging around and here are some other responses from other people having same problem as myself:
starts with -
"We just bought a 1991 2500 3/4 ton Suburban. Yesterday it started missing (I guess that is what they call it) As you drive down the road between 45 55 it starts bucking almost like it loses power. when I speed up it does fine going uphill at 70 it starts doing it again. Someone said to replace the ignition module is this correct. I put new plugs, wires, o2sensor egr valve cap and fuel filter on about 600 miles ago this has the efi system. Please help I am not that familiar with the 454 motor and the efi system. I have also heard that the dist. shaft cam wear out on these engines. would that cause this type of problem."
then the 2 responses:
"My 91 454 did the exact same thing. Had a miss at a certain MPH range.
Mine acted up between 57 and 65 mph, before or after this range it ran like a top.
The fix was a new distributor. As you've heard, the bearings wear out and the distibutor shaft wobbles. At specific rpm's it caused the miss which corresponded with the mph range.
Good as new, once replaced. "
and
"I'd second the distributor. Sounds like you've hit most of the other items. Understand the Throttle position sensor can also be a nominee after about 65-75,000 miles or so."
from http://www.campingworld.com/cforum/i...g/12901293.cfm

i will probably still do the EGR to be safe but the whole distrubutor will also be down the line if the EGR doesn't fix it...
also if the dist is the problem then how hard is it to replace? I am mechanically inclined but i don't know what to do, should i take it to a mechanic or try it myself?

05-30-2005, 04:47 PM	#8
screwballl Tonawanda 454 Join Date: Mar 2004 Location: Liquid Sunshine State Posts: 2,755	ok i did some digging around and here are some other responses from other people having same problem as myself: starts with - "We just bought a 1991 2500 3/4 ton Suburban. Yesterday it started missing (I guess that is what they call it) As you drive down the road between 45 55 it starts bucking almost like it loses power. when I speed up it does fine going uphill at 70 it starts doing it again. Someone said to replace the ignition module is this correct. I put new plugs, wires, o2sensor egr valve cap and fuel filter on about 600 miles ago this has the efi system. Please help I am not that familiar with the 454 motor and the efi system. I have also heard that the dist. shaft cam wear out on these engines. would that cause this type of problem." then the 2 responses: "My 91 454 did the exact same thing. Had a miss at a certain MPH range. Mine acted up between 57 and 65 mph, before or after this range it ran like a top. The fix was a new distributor. As you've heard, the bearings wear out and the distibutor shaft wobbles. At specific rpm's it caused the miss which corresponded with the mph range. Good as new, once replaced. " and "I'd second the distributor. Sounds like you've hit most of the other items. Understand the Throttle position sensor can also be a nominee after about 65-75,000 miles or so." from http://www.campingworld.com/cforum/i...g/12901293.cfm i will probably still do the EGR to be safe but the whole distrubutor will also be down the line if the EGR doesn't fix it... also if the dist is the problem then how hard is it to replace? I am mechanically inclined but i don't know what to do, should i take it to a mechanic or try it myself? __________________ 91 Chevy Suburban Tonawanda 454 R2500 - SOLD!!! 04 Dodge Durango 5.7L Hemi 2WD, 24K miles (as of July 2011) In the past 30 years about 90% of Fords are still on the road, the other 10% made it home. ------------------- Last edited by screwballl; 05-30-2005 at 04:51 PM.