4.9 V6 Missing and Acceleration Problems
#1
4.9 L 6Cyl. Missing and Acceleration Problems
Engine now has a random dead miss during acceleration and seems to do this after the engine has warmed up for about 20 minutes. It accelerated by itself on me this morning, then began to lose power immediately. The check engine light came on immediately when this happened. After I pulled over and shut it off, it acted normal and has since this morning. I'm not much of a mechanic, but I have Chilton manuals for it and can fix it if I have the right instructions without having to replace every part to troubleshoot. The truck has 148,500 miles on it and I bought it new in August of 92'. I love it and will not get rid of it.
Last edited by sawfish; 03-12-2005 at 10:11 AM.
#2
First, you need to pull the codes. You can do this by finding the EEC self test connector in the area of the fenderwell behind the air filter. Pull the little gray single wire pigtail out, and jump a wire from this pigtail to ground. Turn on the ignition and count the check engine light flashes. You have two-digit codes. Example, two flashes, pause, one flash. Code 21. No need to start replacing anything until you have the codes. Repost with codes and can help more.
Robbie
Robbie
#3
Thanks...the same thing happened to me yesterday. First the miss, then total loss of power and I had to coax it over to the side of the road and then it went back to normal. Today it ran like a new truck with only a couple of burps. Thanks for the info...I will do it. Also I replaced the air filter and breather, but I looked for the PCV and cannot put my hands on it. Chilton manual says it's on the left side of the engine under the intake, but I cannot see it. Thanks again for the help.
#4
The pcv is on the top of the valve cover behind the upper plenum below the egr tube. Check the fuel pressure. The test fitting is behind the plenum on the pass. side. It may have a black cap screwed to it. Press should be 60 psi. You could have a fuel pump going bad. First, you need to get the codes!
Robbie
Robbie