97chevy350
Heavy Duty Member
Posts: 524
Registered:
12/19/05
Status:
Offline
From: WV
Truck: 1997 1500
Mods: 4
|
10/29 8:11a
|
|
Truck is a 99 silverado, 5.3 L, 4WD. I Changed Fuel Filter and PCV a few days ago when I changed the oil. Now I have a problem, hesitation when taking off (slow acceleration) and it sometime stumbles around 3,000 rpm. It is not consistent, sometimes it will be a slight hesitation and other times it will just about fall on its face. Also, I can hear the valves pinging, I ran water remover through and also put in a full take of 89 instead of 87 and I am still having problems. Ran the codes and it said EVAP system malfunction (not leak) and yes the gas cap is tight. I can not find a loose vacuum line, I can not think of anything else to look at... any suggestions?
|
|
Stevens07 
Supercharged SS Member
Posts: 14,721
Registered:
3/18/03
Status:
Online
From: PA
Truck: 2007 Sierra
Mods: 14
|
|
10/29 8:43a
|
Have you cleaned your MAF sensor and any possible "coking" in the throttle body 
|
|
97chevy350
Heavy Duty Member
Posts: 524
Registered:
12/19/05
Status:
Offline
From: WV
Truck: 1997 1500
Mods: 4
|
|
10/29 8:56a
|
|
Not recently but it started all of a sudden, I would have noticed something like that. Plus I got the codes P0440, EVAP system malfunction and P0443 evap control system, purge control circuit malfunction....any ideas here? I checked for loose vacuum line and couldnt find any....
|
|
redvett94
Member
Posts: 26
Registered:
1/3/09
Status:
Offline
From: MI
|
|
10/29 6:10p
|
|
This problem apparently started after you changed the fuel filter so i would put another one on you may have a defective on or its on back-wards.
|
|
Paul B
Heavy Duty Member
Posts: 933
Registered:
4/2/05
Status:
Offline
From: CA
|
|
10/30 9:27a
|
|
I`ve heard a saturated or clogged evap. filter can cause these kinds of codes. I`ve never had the problem but our shop mechanics have seen it.
|
|
97chevy350
Heavy Duty Member
Posts: 524
Registered:
12/19/05
Status:
Offline
From: WV
Truck: 1997 1500
Mods: 4
|
|
10/30 6:52p
|
|
I appreciate the input, I think I am going to put another filter on it, though it seems strange to have a defective fuel filter, and I was sure not to put the new one on backwards, even went back and checked to be sure.
|
|
97chevy350
Heavy Duty Member
Posts: 524
Registered:
12/19/05
Status:
Offline
From: WV
Truck: 1997 1500
Mods: 4
|
|
11/5 10:53a
|
|
UPDATE: I changed the fuel filter again... no help. After clearing the codes before, the light came back on after a few days. New code: P0101 : MAF Circuit A Range/Perf Problem. Went ahead and cleaned the MAF, didn`t help, if anything it made it worse. For those that are experienced with this code, is it likely that I need to replace the MAF Sensor?
|
|
Vortec-6000
SS Member
Posts: 2,029
Registered:
12/11/03
Status:
Offline
From: PA
Truck: 2004 2500
Mods: 7
|
|
11/5 11:12a
|
|
Make sure you didn`t knock the plug off of the MAF when you did the PCV valve. Maybe it just came unplugged. Those rarely go bad. The filament looks like a light bulb filament in it. Can you see if it is broken in anyplace? Unless it was removed it has that honeycomb in front of the sensor and maybe behind it too. I usually remove those myself. They protect the filaments from getting hit, but they slighlty impede airflow.If the honey comb is there you won`t get a good look at the filament. If it is there and you have a set of snap ring pliers you can pull the snap ring out and remove the honey comb and get a look at the filament. Or you could just read out the resistance of the pins with a multimeter if you know which pins to check. You would probably need a wiring schematic. If the resistance is farely low it is likely it isn`t broken.
|
|
robt34
Silverado Member
Posts: 423
Registered:
10/29/07
Status:
Offline
From: TX
Truck: 2002 Silverado
Mods: 17
|
|
11/5 5:07p
|
|
Did the problems start after the pcv valve install? When I changed mine I got the same code a few days later and it ended up being a bad pcv valve.
|
|
97chevy350
Heavy Duty Member
Posts: 524
Registered:
12/19/05
Status:
Offline
From: WV
Truck: 1997 1500
Mods: 4
|
|
11/6 11:12p
|
To answer both of the questions, Yes, the honeycomb is removed. I did it myself but I used another (factory) sensor. The original one still has the honeycomb in it and I am going to try to swap them out (The original is back home and Im having it shipped down here in the next couple of days).
And yes, the problem started after the new PCV valve (same time as fuel filter). It rattled like it should when I put it in, could it still be defectice?
|
|
redvett94
Member
Posts: 26
Registered:
1/3/09
Status:
Offline
From: MI
|
|
11/7 7:16a
|
|
Is the PCV an AC Delco? If not it may not be the correct size restriction and allowing too much air to pass by.
|
|
