Vbb199
B-rate Hillbilly Customs
- Joined
- Jan 12, 2018
- Posts
- 9,045
- Reaction score
- 15,338
- Location
- Salisbury NC
- First Name
- Vince
- Truck Year
- 89, 79
- Truck Model
- 89 Suburban R1500, 79 C10
- Engine Size
- 350, 502
Ok, so most of you heathens know me, "hi my names vince" (waves)
Im not a total caveman when it comes to our trucks, and im namely the most familiar with the 87-91 tbi trucks.
My problem stated in the title isnt like "all of a sudden" , its gradually getting worse i feel.
I have some ideas as to whats going on, but im looking for suggestions to bounce off of.
List of work done so far to eliminate anything
Tbi overhaul
Motor is crate motor, with 30k miles, makez 330/385 at the crank.
New iac with relearned idle
I recently checked resistance at TPS, no issues.
New cts
New knock sensor (was causing issues)
Ignition module replace with another oem (old died)
New cap, rotor, plugs, wires, less than a year ago
(I dont drive alot, so no reason to suspect them as being excessively worn)
Exhaust redone, cat delete, straight 3" pipe into flowmaster 40.
Motor makes steady 22hg at idle. (Just checked)
New 700r4 built for 600hp
I just checked to make sure a plug wire didnt come loose (no misfires anyways)
1. What i suspect?
My EGR doesnt hold a vaccuum anymore (worn diaphragm) so as a result i get random egr codes at times, so its possbily causing issues When it attempts to pull a vaccuum at the egr module.
(Considering duct taping vacuum gauge to windshield and going on drive @ 55mph to see if i suddenly lose vaccuum)
2. Ignition module thats worn out (came from another tbi motor)
The power is every bit there on the low end.... i can flat leave about anything from a stop, but top end really sucks butt, if i downshift to 3rd or 2nd, and give it mid throttle, it climbs EASILY 20mph in seconds.
But anything at wot: its not exactly where it once was. Something has changed.
There is no engine codes atm.
Anyone with actual exp in tbi motors have a suggestion?
@1987 GMC Jimmy
(Sorry for pinging you buddy, but you're knowledgable on these as well)
Im not a total caveman when it comes to our trucks, and im namely the most familiar with the 87-91 tbi trucks.
My problem stated in the title isnt like "all of a sudden" , its gradually getting worse i feel.
I have some ideas as to whats going on, but im looking for suggestions to bounce off of.
List of work done so far to eliminate anything
Tbi overhaul
Motor is crate motor, with 30k miles, makez 330/385 at the crank.
New iac with relearned idle
I recently checked resistance at TPS, no issues.
New cts
New knock sensor (was causing issues)
Ignition module replace with another oem (old died)
New cap, rotor, plugs, wires, less than a year ago
(I dont drive alot, so no reason to suspect them as being excessively worn)
Exhaust redone, cat delete, straight 3" pipe into flowmaster 40.
Motor makes steady 22hg at idle. (Just checked)
New 700r4 built for 600hp
I just checked to make sure a plug wire didnt come loose (no misfires anyways)
1. What i suspect?
My EGR doesnt hold a vaccuum anymore (worn diaphragm) so as a result i get random egr codes at times, so its possbily causing issues When it attempts to pull a vaccuum at the egr module.
(Considering duct taping vacuum gauge to windshield and going on drive @ 55mph to see if i suddenly lose vaccuum)
2. Ignition module thats worn out (came from another tbi motor)
The power is every bit there on the low end.... i can flat leave about anything from a stop, but top end really sucks butt, if i downshift to 3rd or 2nd, and give it mid throttle, it climbs EASILY 20mph in seconds.
But anything at wot: its not exactly where it once was. Something has changed.
There is no engine codes atm.
Anyone with actual exp in tbi motors have a suggestion?
@1987 GMC Jimmy
(Sorry for pinging you buddy, but you're knowledgable on these as well)
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