I have an 03 Isuzu ascender 4.2 with 170k miles it sat for 2.5 years before I got it. I did a full service besides plugs and coil packs. I changed engine oil and trans fluid twice and the first time flushed with seafoam. Put new tires on it and I've had it about 9 months. The only few problems I've had to replace #4 coil pack, had the headlight relay fail and melt and i had to replace the radiator. About a month after I bought it a noticed a a high tone humming noise coming from the driver side for about 10 seconds on start up like an electric motor sound. When it stops you hear it wine down and the oil light stays on for about 8 in the process. I never thought too much of it till my wife was waiting in line to pick up the kids from school and the oil pressure went to 0, check gauges light came on, and the oil light came on. Lasted about 3-5 seconds and everything went to normal. Anyone know what could be up???
Whine noise on startup
- Thread starter Johnboy91
- Start date
Mooseman
Moderator
Hi and welcome. I changed your thread title to get more responses.
That sounds like it's the SAIS (secondary air injection system) if you have one. 2002 didn't have it but not.sure when they started. It is mounted on the passenger side of the head right above the exhaust manifold. It sounds exactly like you said, kinda like a small vacuum cleaner when cold. This is very normal.
For the oil pressure, it's likely the pressure switch that's failing. Cheap enough to just replace. It's located just above the oil filter.
That sounds like it's the SAIS (secondary air injection system) if you have one. 2002 didn't have it but not.sure when they started. It is mounted on the passenger side of the head right above the exhaust manifold. It sounds exactly like you said, kinda like a small vacuum cleaner when cold. This is very normal.
For the oil pressure, it's likely the pressure switch that's failing. Cheap enough to just replace. It's located just above the oil filter.
Mounce
Member
Agreed on both. The air pump motor is located on the driver side under vehicle I've heard around the drivers seat area and is plumbed over to the pass side of motor.
Wooluf1952
Member
In case you haven't heard:
http://gmtnation.com...eres-the-story/
I believe the SAIS started on the 2004's. I know for sure my 2003 Envoy does not have it.
Mooseman
Moderator
This thread has pictures of the said valve and hose attachment.
https://gmtnation.com/forums/threads/p0410-code.355/
https://gmtnation.com/forums/threads/p0410-code.355/