SparkyJJO
Lifer
OK having had one of these for nearly 6 years, and having had 215k miles of service from it...
1) There is only ONE upstream sensor. It is an inline 6, so there is one sensor in the manifold (pop the hood and look at it, easy to spot), one sensor post-cat. Don't bother with the post cat sensor unless it fails, it does nothing aside from monitor the cat (this goes for any post-cat sensor, really). Get AC Delco for it, or Denso since Denso actually made the sensors for AC Delco for a while.
2) There are no plug wires. They are coil on plug. They are also really easy to get to so to help troubleshoot a misfire, swap coils around. #1 is the closest to the radiator, #6 is it closest to the firewall. If you find you have a bad coil, replace it, but I wouldn't bother replacing all of them. My 2002 had all original coils after 14 years and 215k miles. While they can go bad, they aren't a routine thing.
3) AC Delco 41-103 spark plugs only. They are iridium so should last 100k miles, although in my experience they can start dropping off around 80k in effectiveness.
4) Stock shocks are squishy, yes. I installed Bilstein HD shocks (yellow/blue). Better, controlled ride. Yes, it is an SUV, not a car, but it is also the first of its class to not require rollover warnings because unlike the others it has a lower center of gravity and is very stable.
5) Wheels are a 6x5 bolt pattern, which almost no other GM platform uses (thanks GM, actually I blame Isuzu for that one since they had a hand in the platform development). S10 blazer wheels will not fit.
6) If it is 4x4, the transfer case fluid should be changed every 50k. If it hasn't been done, do it. Only use GM Autotrak II fluid, about 2 bottles. The drain/fill plugs on the case use 10mm allen wrenches.
7) Cleaning the throttle body is a good idea. Disconnect the battery, take off the intake tube, disconnect the vac line and the electrical plug, 4 bolts, and it is off. Use throttle body cleaner and a rag and shine the sucker up.
8) Fan not blowing on a speed is usually a resistor problem, but since that is bypassed on speed 5 (full tilt) that isn't likely it. I can't remember exactly but I want to say speed 5 used a different fuse for some reason.
9) If you want to lift it, be careful of some lifts out there. Because of the independent suspension design and CV axles up front you have to use a "preload" style of lift/level, not just a spacer you stick on top of the strut assembly, unless you want to destroy the CV shafts and the ball joints from over extension. Speaking of which, above approximately a 30" tall tire (depending on width) you will need to run wheel spacers in order to push the tires outward a bit to clear the upper ball joint. I think it looks better anyway as the wheels are now more flush with the wheel wells instead of inset. It also makes it a little more stable feeling just because of the now widened track width. Obviously spacers can introduce their own set of possible issues, but for both lift components and wheel spacers I strongly recommend theliftmeister.com - one of the originals developing lift parts for this platform.
10) Check out GMTNation.com for all sorts of stuff related to the platform. Trailvoy turned into a ghost town when Vertical Scope bought the site and neglected to fix problems and, well, it was ugly. Almost the entire mod staff and a majority chunk of the membership left to create the new site a few years back.
For reference, here are some pics of my old 2002, pre lift and post lift.
1) There is only ONE upstream sensor. It is an inline 6, so there is one sensor in the manifold (pop the hood and look at it, easy to spot), one sensor post-cat. Don't bother with the post cat sensor unless it fails, it does nothing aside from monitor the cat (this goes for any post-cat sensor, really). Get AC Delco for it, or Denso since Denso actually made the sensors for AC Delco for a while.
2) There are no plug wires. They are coil on plug. They are also really easy to get to so to help troubleshoot a misfire, swap coils around. #1 is the closest to the radiator, #6 is it closest to the firewall. If you find you have a bad coil, replace it, but I wouldn't bother replacing all of them. My 2002 had all original coils after 14 years and 215k miles. While they can go bad, they aren't a routine thing.
3) AC Delco 41-103 spark plugs only. They are iridium so should last 100k miles, although in my experience they can start dropping off around 80k in effectiveness.
4) Stock shocks are squishy, yes. I installed Bilstein HD shocks (yellow/blue). Better, controlled ride. Yes, it is an SUV, not a car, but it is also the first of its class to not require rollover warnings because unlike the others it has a lower center of gravity and is very stable.
5) Wheels are a 6x5 bolt pattern, which almost no other GM platform uses (thanks GM, actually I blame Isuzu for that one since they had a hand in the platform development). S10 blazer wheels will not fit.
6) If it is 4x4, the transfer case fluid should be changed every 50k. If it hasn't been done, do it. Only use GM Autotrak II fluid, about 2 bottles. The drain/fill plugs on the case use 10mm allen wrenches.
7) Cleaning the throttle body is a good idea. Disconnect the battery, take off the intake tube, disconnect the vac line and the electrical plug, 4 bolts, and it is off. Use throttle body cleaner and a rag and shine the sucker up.
8) Fan not blowing on a speed is usually a resistor problem, but since that is bypassed on speed 5 (full tilt) that isn't likely it. I can't remember exactly but I want to say speed 5 used a different fuse for some reason.
9) If you want to lift it, be careful of some lifts out there. Because of the independent suspension design and CV axles up front you have to use a "preload" style of lift/level, not just a spacer you stick on top of the strut assembly, unless you want to destroy the CV shafts and the ball joints from over extension. Speaking of which, above approximately a 30" tall tire (depending on width) you will need to run wheel spacers in order to push the tires outward a bit to clear the upper ball joint. I think it looks better anyway as the wheels are now more flush with the wheel wells instead of inset. It also makes it a little more stable feeling just because of the now widened track width. Obviously spacers can introduce their own set of possible issues, but for both lift components and wheel spacers I strongly recommend theliftmeister.com - one of the originals developing lift parts for this platform.
10) Check out GMTNation.com for all sorts of stuff related to the platform. Trailvoy turned into a ghost town when Vertical Scope bought the site and neglected to fix problems and, well, it was ugly. Almost the entire mod staff and a majority chunk of the membership left to create the new site a few years back.
For reference, here are some pics of my old 2002, pre lift and post lift.
