On a1999 chev 2500 4+4 /454 no matter where I put the shift lever it wants to go ahead

[rusty]

Hi
I got chevy cheyene 4x4. some years ago replaced key n tumbler. Then bout a year ago the security light would start flashing and the truck would start,only to shut off right a way. I learned to turn key on and leave for 10 min or so then turn off, pull key, then start. if light was still flashing i wud have to start the process over. Bout 2 monthes ago had key n tumbler swaped out of wrecked truck into mine. This helped for a while but now it is a problem again. How can I kick this problem???????????
Thanks, Rusty

[TerryAuto]

Your truck does not have a problem in the ignition key cylinder (tumbler), it is a problem in the passlock sensor. This is the aluminum housing that the ignition cylinder sits in. The sensor reads the key and controls the theft system. Either that, or a bad connection on the wiring harness from the ignition that goes down the steering column and connects to the dash harness. Could be a loose connection in that connector, or a wire rubbing on the column. Tilt the wheel up and down while cranking to move the wiring around to see if that causes or fixes the problem.

[rusty]

Thanks for the suggestions. Will check that out.

[kwbush]

Got a 1995 Silverado whose service engine soon lite just came on. Along with the lite came an increase in engine idle speed (600 rpm to 1200 rpm) and the automatic tranny bangs into gear so hard it pushes me back in the seat. The other gear shifts are progressively gentler but still harder than normal. Online I was told the shifting problem was caused by a faulty TPS (throttle position solenoid) which I changed but all remains the same.

Any advice as to what to try next?

1995 Silverado 5.7 l, automatic, 2-wd, C-2500 has a set of headers and a towing cam, can't seem to locate an O2 sensor but the truck, until last week, ran perfectly fine.

[carriedi]

you're going to need to scan the computer for the code. when the service engine soon (SES) light comes on a code is usually stored in the computers memory. Most cars or trucks will run differently when the SES light is on. It runs differently because instead of using the inputs the computer usually sees to make everything run normal it will put in a substitute value for the input that it sees as not being right. Of course the value it makes up is not really correct, it is just a value to keep the engine running so you don't get stranded on the road somewhere. So, scan for the code and start from there.

as for the symptom, higher than normal idle, can be a few things. when you scan for codes look at your fuel trims, your O2 sensor and your idle air control (IAC). you could have a vacuum leak that will make the computer add fuel to keep the O2 sensor happy. (which means the idle will go higher because more air and more fuel)

Do you know what the code is for the check engine light?

[ddafternoons]

Hello. I'm having a problem with my son's 1988 350 tbi k5 blazer. It won't go into closed loop. It's idle is too high all the time. We changed the coolant temp. sensor, no difference. Checked the timing, but I knew it wouldn't be the problem, unless it was so far out of spec. that it could be the cause. Timing is not quiet on zero, but this, in my humble opinion, is probably due to the idle problem. I tried to put my dist. wrench on the darn hold down bold but it wouldn't budge. The car had no cat. converter on it when we bought it and it was throwing a code for the egr. I installed, what I believe is a Cal. approved converter on it and the code went away. I'm not sure why it say's it's a 3-way cat. when I don't see a air tube at the cat. I always thought a 3-way is supposed to have an air tube at the cat. I did find a hose hanging down from the back side of the engine and I can't seem to see where it's coming from. I've never seen a hose, it's around 5/16" hosing, hanging off a engine that serves no purpose. I pulled the IAC unit, started up the car and put my finger in the hole where the IAC was and the idle dropped. So I figured that the IAC motor wasn't working. Put a new one in and it seemed to run faster. I don't know if I was to do something to introduce the new IAC into the system. I don't show any codes. I sprayed for vaccum leaks and I haven't found any obvious problems. So I was desperate and turned down the throttle screw on the throttle body, even though I know this isn't the correct thing to do, just curious, but it idled down a little but not the answer. I'm not sure if the O2 would help, I haven't checked it, but I would thing if it's not operating properly a code should pop up. I'm not sure if the MAP would cause this problem, but I don't want to shotgun the problem only to find out I'm just guessing and buying parts for the sake of it, hoping it will fix the problem. I will attempt to clean up the ground wire area where the coolant temp sensors grounds but it doesn't look like it's very corroded. Help!!

[carriedi]

I think you should have your truck scanned. you need to see the data stream so you can see what the computer is doing. If you have a vacuum leak of if you have too much fuel in the mix your computer will react to the oxygen sensor and try to make it run clean. (emission wise) Look at the fuel trims and coolant readings. Look at the IAC count. The computer is supposed to control your idle. Find out why it is keeping it so high.

without seeing what the computer is doing, everything is just the shotgun approach. So, depending on how much ammo (money for parts) you want to spend, you could narrow your search by having it scanned.

scanning will tell you the coolant temp status, oxygen sensor responsiveness, iac counts, fuel trims, etc.

[carriedi]

that's a tough one. Nothing you do to fix the crack will last until you find out why it's cracking. If it's a stress crack you will need to find out what is causing the stress. Is the mounting bolts not tight and the dash is sagging? Hes the truck ever been in an accident and the dash mounts tweaked a little bit. Or is the dash plastic just old and brittle? The crack the is coming up by the hump sounds like a stress crack. The crack going across the dash could be from stress or just age. There are compounds that are made for dash repairs. and there is plastic welding repairs. But no repair will be as strong as the original material.Maybe if you were able to bolt something across where the crack to help hold it together it could add more time to the repair.

there are videos on youtube on how to repair plastic dashes. They all entail a lot of time and elbow grease (labor, not real grease) Sanding and smoothing, then painting... Just do a search for "plastic dash repair". Most of the time they will say to remove the dash to do the repair. If you do that, you might want to price out a new (aftermarket if new is no longer available) or used dash unit that isn't cracked and replace it.

I know it probably irritates you like crazy to see it like that but it might be so much work that you will just leave it until you get a new truck. Now I say that because I am old and don't like doing stuff like that anymore but I used to go a go getter and would do that kind of stuff on my vehicles all the time. So, if you are like how I was, 1. start taking the dash apart (if you have another vehicle to drive around). If you don't think it is something you can handle, 2. take it to a shop and get an estimate. 3. It ain't so bad and live with it. Let me know what you're gonna do.

labor time to remove and re-install a dash unit is 7.2 hours. Includes R&I upper instrument panel and console.

Now' if it is one of the panels that attaches to the dash, that would save a lot of time.

[GUEST]

On a 1999 2500 /454 4+4 no matter where I put the shift lever it wants to go ahead, except in park

[carriedi]

Is it in park when you put the shifter in park? I mean is the transmission locked and the truck is unable to move when you put it in park.

with the engine off, do you feel all the detents for all the gears as you move the shifter from park to reverse to neutral to drive 4,3,2,1?does it all feel normal?