1998 Chevrolet Silverado Engine Surge

Tiny
JAMES3980
  • MEMBER
  • 1998 CHEVROLET SILVERADO
  • 5.7L
  • V8
  • 4WD
  • AUTOMATIC
  • 267,000 MILES
Just changed the engine in my truck it runs great, starts and idles normally. But once in awhile it stumbles and surges well driving at 1200-1400 RPM and sometimes does that in slow reverse to. No engine light on for the time being and there was no DTC showing up, but the last time the light went on I put a DTC to it and got a fuel system to lean kinda reading. Any suggestions?
Do you
have the same problem?
Yes
No
Wednesday, July 29th, 2015 AT 5:39 PM

11 Replies

Tiny
JACOBANDNICKOLAS
  • EXPERT
Most all lean mixtures are the result of a vacuum leak. Check that first. Also, you may need a real time scanner to watch how the O2 sensors are reacting and we may need to check fuel pump pressure to make sure it is keeping up with the demand.
Was this
answer
helpful?
Yes
No
Wednesday, July 29th, 2015 AT 7:54 PM
Tiny
JAMES3980
  • MEMBER
No vacuum leaks and all brand new O2 sensors. Do you think it might be a clogged catalytic converter? Because sometimes when going up steep hill the engine stumbles when trying to accelerate causing me to have to punch the paddle harder to get passed the stumbling then smell exhaust fume shortly after.
Was this
answer
helpful?
Yes
No
Tuesday, August 4th, 2015 AT 12:52 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
That is possible. If it smells funny when you have to accelerate heavy, are you sure it isn't getting too much fuel? Have you checked fuel pump pressure to make sure the regulator is working? Also, have you checked the vacuum supply to the regulator to make sure it isn't pulling fuel through there?
Was this
answer
helpful?
Yes
No
Saturday, August 8th, 2015 AT 5:42 PM
Tiny
JAMES3980
  • MEMBER
The heating in my 1998 Silverado quit working. I changed the heater core, blower motor and fuses are still good. Could it be the water pump not working or radiator needs to be flushed?
Was this
answer
helpful?
Yes
No
Thursday, November 26th, 2015 AT 4:41 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
With engine running and warmed up and the heater on high, feel both heater core hoses. If both are hot, the blend air door isn't opening.
Was this
answer
helpful?
Yes
No
Thursday, November 26th, 2015 AT 7:15 PM
Tiny
JAMES3980
  • MEMBER
The hoses did heat up. Now how do I go about getting the door to start opening again?
Was this
answer
helpful?
Yes
No
Friday, November 27th, 2015 AT 3:57 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
If both are getting hot, coolant is flowing through the heater core. Now, the blend air door is located on the heater box under the dash of the vehicle. I believe this one is on the passenger side. Locate the heater box (where the core is located) and then locate the doors that open and close from that location. Once located, actuate the heater control from cold to hot and see if the door reacts.
Was this
answer
helpful?
Yes
No
Tuesday, December 1st, 2015 AT 5:39 PM
Tiny
JAMES3980
  • MEMBER
I changed the blend air door on the driver and passenger side and still nothing, so I inspected the control panel and noticed it was the harness that plugs into the off/on switch was not on properly and would not stay on properly so had to tape it up to make it stay in place so now it is working for now. Do I need a hole new control panel or just change the off/on switch?
Was this
answer
helpful?
Yes
No
Wednesday, December 2nd, 2015 AT 4:15 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Wow! You have the same kind of luck I do. As far as the switch, I believe you can just replace it on this year. The knob pulls off the front and then the switch snapped into position (if I remember correctly). See attached pic I found on the web.
Was this
answer
helpful?
Yes
No
Wednesday, December 2nd, 2015 AT 6:26 PM
Tiny
JAMES3980
  • MEMBER
The heating problem has come back I know what the problem is just need to know what might be causing the on/off switch on the control panel to keep blowing out and frying up the wire harness because these control panels are not keep to replace, had 3 blow out on me now.
Was this
answer
helpful?
Yes
No
Wednesday, April 6th, 2016 AT 2:23 PM
Tiny
JAMES3980
  • MEMBER
They not cheap I meant to say.
Was this
answer
helpful?
Yes
No
Wednesday, April 6th, 2016 AT 2:24 PM

Please login or register to post a reply.

Recommended Guides