Chevy & GMC Vans

Hey everyone,
Been reading all the trouble shooting info and have got some good input but need a little more beta if possible.
I have a 99 Safari AWD and need a little help with some trouble shooting. Two issues are going on.
1. it has 130,000 miles and has been running great other than when idling it has a crazy surge. Surges really high and then drops down to normal. Totally rhythmic and constant.

2. This just happened yesterday as I was driving home from a road-trip. The van was running fine, started to bog and then just died. Started right up and would only drive very slow and any push on the gas pedal would cause it to die. Limped it 30 miles (over 2 hrs) to a gas station. Filled the tank up with premium (6 gallons needed to top it off) and added some octane booster. Started right up and made it 100 miles home before the same issue happened again.
I read in a previous post that maybe a new Ignition Control Module and pick up coil would be a good trouble shooting fix.
Any and all info would be great. Thanks so much. Cheer, Atom....
PS, my gas mileage also sucks. 13-14 mpg

Just ran the codes
Codes showing up are P0131, P0151, P0327 (is there a place I can find what the codes represent?)
Thanks again, Atom...

Just use google (or you favorite search engine) to look the codes up. P0131 and P0151 are oxygen sensor codes and P0327 is a knock sensor code. The symptoms you describe shows it is probably the knock sensor.

Thanks for the info. Going to the auto store in the am. Appreciate your help. Atom....

LiftedAWDAstro wrote:Just use google (or you favorite search engine) to look the codes up. P0131 and P0151 are oxygen sensor codes and P0327 is a knock sensor code. The symptoms you describe shows it is probably the knock sensor.

I must be an idiot I can't find the Knock sensor on my van. The manual says near the Distributor? No luck at all. Any ideas?

LiftedAWDAstro wrote:Just use google (or you favorite search engine) to look the codes up. P0131 and P0151 are oxygen sensor codes and P0327 is a knock sensor code. The symptoms you describe shows it is probably the knock sensor.

at left rear of distributor, on engine block

Thanks, under my very nose. Could have sworn I looked for hours in that very place. Time to take that darn cover off again. Thanks again Atom...

timelessbeing wrote:at left rear of distributor, on engine block

Having major problems with this. So I bought the new knock sensor. Brass looking round item with threads coming out the bottom and a plastic piece on top where a single wire attaches. Looks just like every pic I have seen of a KS. The place that this is supposed to mount according to the manual and the photo you posted has a different part there.
I pulled the part. It has a long screw going through the black round plastic body. Coming off the side of the round plastic piece is the female end that the wiring attaches to. The threads of the screw are way smaller than the threads of the Knock sensor that I purchased. So the new KS would not fit in there anyway.
I am at a total loss. Any ideas? 1999 GMC Safari AWD 4.3L Vortec engine....

timelessbeing wrote:at left rear of distributor, on engine block

Some photos would help big time.

Not that great a photo but it is the bolt with the little green dot on top. That is where everything says the knock sensor should go. To the right is the oil sensor and upper right is distributor. Any ideas? Thanks, Atom...

timelessbeing wrote: Some photos would help big time.

That looks a lot like a 2000 knock sensor.

Check the condition of the wires before you put everything back together.

I went through all the years after 97 at the auto parts store. This is what the part should look like on all those years. I'm at a total loss..

timelessbeing wrote:That looks a lot like a 2000 knock sensor.

Check the condition of the wires before you put everything back together.

this is what I came up with

That is the part. Is it a knock sensor? I have been to 6 different auto part stores and they don't show that part.

timelessbeing wrote:this is what I came up with

yup