HELP!! I am stuck! What happened to my truck!

[junior3382]

Okay, so I took my Blazer in for inspection. Thats all. Also figured it was time for an oil change. I got the reciept, there was NOTHING done for inspection, clean bill. Yet now it runs like CR^P!!! I mean WTF??

Here is the issue. It is skipping at idle. Almost stalling. It hesitetes huge when trying to take off from a stop. When driving though, it runs fine. I just had new wires and plugs installed. Had them for a few weeks now with no issues. There is NO engine light. Brought it back, tested the EGR, TPS and MAP sensors ...we are stumped... according to the computer everything is running fine. Checked to see if any of the wires had slipped off, and negative there. I have no idea what I am doing to this thing! It is like my hands are cursed on this particular vehicle! I have never had stupid little problems like this.

I Know when something does not feel right, and there is something I am missing. I cannot think where else to look. I mean I almost wish there was a light so I can have the truck actually tell me what is wrong.

Any ideas? I am going back to the shop tomorrow, and we are going to take another look at it. It helps this guy is a friend, but we are both stumped. We needed the night to think about it. I also wanted to see what y'all thought! I, like so many here, do not have the money to be throwing at new parts and sensors if it does not help.

The motor and electronic componets are covered under a great warranty, but only for another 989 miles, I am pushing my luck. If something is going to go, minor or major, it better go NOW! So, while these things are covered, I want to nip this in the butt. When we examine this again tomorrow, i want fresh ideas, so any help here is greatly appreciated. And if/when we fix this, I will also be sure to post back what it was, like I preach others to do

[Sneakysportsman]

I hope this is the 98 Blazer you are talking about.
You may have some bad poppit nozzles in the injection spider. If they are going bad there is no way the ECM can detect it unless it shows a code in the rich or lean catagory. You may have a bad intake plenum gasket or leak.

[gmctrucks]

Jr. did they disconnect something while doing the inspection sticker maybe placed the wrong gas cap on your truck while they tested it? Maybe some bad gas, bad battery, or ground, or connection. Keep us posted.

[crabtruck]

timing wire still disconnected/loose ?

[junior3382]

Correct gas cap, has a key, and I used it. Engine light is not on....

Checked all the wires myself, all on tight. As far as i know, nothing was disconnected. There was no need. I doubt they even popped the hood, oil change and inspection were not done at the same place. My guy does not have an inspection liscense. And I thought about this, but I doubt it has anything to do with emmisions due to it passing the state required test. ECM gets tested and exhaust. Perhaps the test burnt the EGR, but wouldn't that send a signal for the engine light? And besides, we tested the EGR and test was clean.

I am up now, and after a nice hot shower, I am heading to the shop. It is probably something really stupid and I am simply drawing a blank, but meanwhile, let me know what else makes sense.

[03chevy]

have you checked this stuff??
1Inspect Wireset Damaged, worn, or deteriorating spark plug or coil wire(s). 2Inspect Spark Plug Fouled, damaged or broken spark plug(s). 3Inspect Spark Plug Gap Incorrectly gapped spark plug(s). 4Inspect Timing Specification Incorrectly adjusted engine timing. 5Inspect Air Filter Restricted or clogged air filter. 6Inspect Fuel Filter Clogged or dirty fuel filter 7Inspect Distributor Cap Loose or cracked distributor cap 8Inspect Rotor - Ignition Damaged, worn, or corroded ignition rotor. 9Inspect Choke Thermostat Stuck or improperly functioning choke thermostat. 11Inspect PCV Valve Plugged or damaged pcv valve. 12Inspect Throttle Position Sensor Faulty throttle position sensor or throttle position sensor circuit. 13Inspect MAP Sensor Improperly connected or faulty m.a.p. sensor. 14Inspect Idle Speed Control Actuator Damaged, loose, or faulty idle speed actuator. 15Inspect Idle Air Control Valve Damaged, loose, or faulty idle air control valve. 16Inspect Fuel Pump Improperly functioning fuel pump or circuits. 17Inspect Fuel Injector Plugged, dirty or poorly connected fuel injector. 18Inspect EGR Valve Clogged, dirty or improperly functioning or defective egr valve. 19Inspect Distributor Worn, loose or incorrectly adjusted distributor. 20Inspect Camshaft Worn or scored camshaft lobes may affect proper fuel intake, compression, combustion and exhaust.

[junior3382]

03chevy, where did you get that? Seems like it was taken straight from a book....

I just got back, spent almost two hours hunting. However, on my way in, the engine light finally came on. And I was right it was a stupid problem, I am almost embarrassed to post it here. I feel like a flippin' idiot!

The code read it was running too lean, so we imediately jumped to mass air flow and throttle position. Even got it running worse at one point! However, no visibale problems there.

However, and here is the kicker.... we went to remove the air intake cover to get to the TPS, and low and behold, the little hose running into the back was not connected! We felt like morons! Simply pressed it into place while it was running and it was like night and day, truck settled into a nice purr.

STUPID VACUUM LINES!!!!!!!!!!!!!!!!!!!

I am not a fan, can you tell? LOL... anyways, good news is, it was not my fault, and it was no parts required, so no cost! I must be losing my mind, I mean why did I not think of a vacuum hose?

O well. I can rest easy now. And I think it is almost time for my nap anyways...LOL.

[03chevy]

almost from a book.. if you go to autozone.com and do the add a vech. then go to repair guides. very help full sometimes but not on everything

[Chevy_Finatic79]

Usually a loose vacuum hose makes it idle really high in park or neutral and almost die in in gear wierd that it didnt in your case JR.

[gmctrucks]

Jr. my trucks gas cap didn't pass the inspection but I still use it I need to buy another one every once and a while it sets my check engine light on I thought that it was my EGR but I think it's the bad cap. I hope you find the problem run a Seafoam it might be carbon on that EGR. Good luck! GMC