1995 Ignition Switch Blues, need help to change...

[john8662]

The problems:

My 1995 K2500 burb has has some quirks to it for some time that seem to be getting worse. The problem is that at an intermittent time driving down the highway in overdrive with the TC locked the burb would have a glitch. The glitch was what you would call either a skip, buck, or cut-out. The skip is so quick that I don't notice any change in the gauges. It would cut out for just a sec, all it would do is make a jerk feeling though the cab. This would happen very intermittently, sometimes it wouldn't do it for weeks.

At first I though that it could be the transmission TC unlocking. So I the pulled codes for the engine and transmission. I didn't get any codes whatsoever besides the test code. I really didn't believe that it was the TC unlocking, because if it unlocked it wouldn't be a very very quick jerk, it would be a jerk, and then a re-engage of the TC clutch.

Next I went though all the fuel system checks. I installed a new oil pressure switch thinking that maybe the electric lift pump wasn't getting current to generate enough fuel pressure, maybe causing the engine to cut-out. Also, my oil gauge inside responds strangely, doing 2400rpm I usually see 55psi oil pressure, the gauge will dance between 55psi and 75psi, the gauge would bounce between the two, in 2 second intervals. This happens sometimes, not all the time, sometimes it works normally. So, I drove the burb a couple more weeks after changing the OPS, during that time it did the skip again, so that wasn't it, and the gauge still does its thing occasionally. Without a fuel pressure gauge or access to one, I opened the air bleed valve on the front of the engine to see if the engine would die because of a lack of fuel pressure while running. It didn't, so the lift pump was working. But just to be sure that I was getting maximum pressure from a good pump, I replaced that (expensive little turd). I was thinking at the time that for some reason I might not have the right fuel pressure to supply the injection pump, so when the system got behind that it could cause the skip and then the system would catch up again (fuel pressure would rise). Its was a theory none the less, didn't solve the problem though. Next I changed the "o" rings on the bottom of the fuel filter bowl, trying to find a source of air getting into the system that could cause the skip, and then installed a new fuel filter. Did that fix it, nope, still does it on occasion. So, I have exhausted what I thought could be the problem. The injection pump could be the culprit, but no codes, the FSD was new when I got the burb, so thats probably not it, it doesn't die, runs great.

So, in my troubleshooting I have given up on the problem until it gets worse and more consistent, thats why I am writing this. Its more and more common now with other symptoms that now point to the dern ignition switch. I have after-market gauges in the burb, isspro. I have noticed that lately they have been acting funny and that the skip is more common now, does it every day. I have noticed that when it skips, that the gauges (isspro add-ons) will reset, and jump. So I am led to believe that the problem lies in the ignition switch that powers everything.

Now the questions.

1.) Could someone that has changed the ignition switch themselves point me in the right direction to doing it myself? I am mechanically inclined, just need some pointers to save some time and confusion. So...

2.) What tools will I need (other than the ordinary sockets and standard and phillips screw drivers)?

3.) What all has to be dismantled to gain access to the switch (not the key tumbler)? The dash? the plastic under the column (part of the dash.)

4.) Do you have to remove the steering wheel? If so, how and what tools, airbag?

5.) I can't remember a specific situation, but I have read on TDP of a possible broken ground wire on the wiring harness associated with the ignition as being a source of problems. If I am talking about the right thing, I want to check for this while I am there.

Thanks for your help, sorry for the history of my troubleshooting, just a reference.

[MTTwister]

John - while waiting for a definitive reply - try a search on ignition switches - there have been a few helpful hints buried out there.

My '96 would miss occassionally, and my cruise would drop out. Dealership, after a couple of years, they kept it for 3+ days, and traced it to the IP and replaced. It was also probably the FSD transistor problem, but it was their dime. Well- almost, they got me for a Lift pump.

Just 'cause the FSD was 'new' doesn't necessarily mean it doesn't have the 'loose -nut' syndrome on the transistors.

However, I didn't notice anything with the dash gauges at the time - don't have the Real gauges in yet.

Did you check all your Grounds- btw?

[patrick m.]

the ign switch is a source of many troubles for the 95 models, i have been there too.
it is very easy to replace, you will need a small set of "torx" bits to remove the steering column shroud just behind the steering wheel, you will also need some "inverted torx" bits to remove the switch itself, all of the other tools are pretty much standard.
the switch has a section of harness made on to it to reach down the column to the main harness, it is held in place with wire ties, and the connector is a "bolt-on" design ( i think the bolt has an 8mm head).
toughest part about the job is paying for the switch

[john8662]

Patrick,

Thanks for your reply on the switch. I wanted a tools list before I got started, its such a pain to get started and not have what you need. Most times I spend more time chasing tools and parts than actually doing the work. didn't realize I needed inverted torx bits, I'll look for those. Thanks for the hints, I didn't know what all had to come apart, these aren't like the old style colums like whats found in my 86. Thanks again.

John