OBD II codes P0108 & P0410;Engine cranks but won't catch

Question

'99 GMC Suburban 5.7L V8;
OBD II codes P0108 & P0410;
Engine is cold and weather is cool & damp;
Engine cranks but won't catch; sounds like it fires occasionally, but won't sustain.
After releasing the ignition switch, engine rocks backwards a bit.
This is a new-to-me vehicle; the other time I tried driving it, weather was hot & dry and it worked OK. Also, while hot, drove through heavy rain and it worked OK.

Probably unrelated: while climbing moderate hills at 45 to 55 MPH, engine feels like it stutters or the transmission is trying & failing to downshift.

Lance ==)------------------

Answer 1

Hi there,

The code P0108 indicates an issue with the manifold absolute pressure sensor. Here is some info for this code.

P0108 GMC - Manifold Absolute Pressure/Barometric Pressure Circuit High Input

Read more: https://www.autocodes.com/p0108_gmc.html

The code P0410 indicates an issue with the air pump solenoid. Here is some info for you.

P0410 VOLKSWAGEN - Secondary Air Injection System-Pump Relay Fault

Read more: https://www.autocodes.com/p0410_volkswagen.html