I have been surfing for 2 days and have not found the same symptoms on here. PLEASE HELP !!!!
Okay car started with maybe a small misfire? and grew worse. It started a small backfire at low RPM under load and progressed to multiple backfire and violent shaking. I was able to drive it at high RPM like 75 MPH inn 5 th gear 60 MPH in 4, but it still had a shake to it if I gave it any extra gas it would backfire.
Fuel pressure is good, I pulled all plugs they look good, all wires are in tackt. Car idles fine does'nt die out, sounds good if you rev it, but under load it just pops like crazy.
Also have no idea if related but my lights won't pop up or turn on, driving lights and fog lights are on though.
Any thoughts Electrical or fuel or Opti.
It almost seemed like a cylinder or 2 was not firing and dumping all the fuel into the exhaust, but all spark plugs were good no wet or oily.

 

Maybe one of your sensors is unplugged? We unplugged mine one time by mistake when we changed the plug wires and it went crazy like you're saying. I'm thinking it was the knock sensor.

 

I'll check it out. Not the knock sensor in the computer though right. the in the engine bay ? WHERE IS THAT ONE located ?

 

Take a look at the coil and see if it has holes, or splits or tell tale white spots of shorting. If it hasn't been changed in a while, change it.

 

Changed the Knock sensor, plugs, and new ignition coil, and fresh gas. Runs a bit better but still has a stumble and a small backfire( under load in low rpm at take off), also has a bit of a shake at take off.
Any other sugestions????
I still think it is missing.

 

MAF, MAP or O2 sensors...
It sucks I know, I been through it.

 

It is not the O2 sensor. How do you check the MAF & sensor

 

You sure its not the O2 sensors?

To check the MAF, swap in one that works and see if it changes anything. Or do a visual inspection to see if any of the little wires are bent or broken. Make sure the screen is intact, and finally use some electric parts cleaner and spray the inside of the MAF.

For the MAP sensor, take a look at it and make sure the green clip is still intact.
http://shbox.com/1/map.jpg
If it is broken, go head and get the new pigtail #12085502. You can check the voltage of the MAP sensor (Page 4) . http://www.autoshop101.com/forms/h35.pdf

I replaced the whole sensor, seal, and pigtail, just to make sure. Probably not necassary though.

 

Replaced the map sensor nothing, replaced the mass air flow nothind it has new O2 sensors. I brought it to diagnostic test nothing. The mechanic said he thinks it is a burnt valve.

It now has also started to act up at ignition sounds like the starter is not engauging.

I am also feeling a "thud" internally almost like on a certain point during the revolution. It happens like clockwork I can time it at every say " one one thousand "thud" one one thousand "thud"........Not a loud thud or a metel crashing maybe sounds like a pencil thumping a melon ???

HELP !!!!!!!

Is it time to rip the heads out for valve Job

 

Okay there is also Oil and/or gas in the throtle body. Not a ton but enough to wet my fingers

 

So car has no PCV valve ? has been like that for at least 2 years.
I bought a PCV and air breater/oil seperator do I use them both or just one of them ??

 

Okay think I found the problem !!!! The opti harness wires were cracked (where it plugs into the opti ) If these wires were sparking to each other would these symptoms occur ??

Also while I have the valve covers off and the intake is there anyway to see if I have a burnt valve ???

All rockers look great and the way they should be.

 

do a compression test...does not sound like a burnt valve, but sometimes a burnt valve will cause the tailpipe to suck every few seconds.

Sounds to me like an ignition problem, how old it the opti coil/ etc...check all that stuff. PCV is on the side of the intake manifold.

Oil in TB is normall....just clean it.

 

sounds like it was prolly your opti harness. another thing that I would recomend is moving your ICM and Coil off the front of the head. Mine had some issues that I thoguht was a bad opti, turns out the head was jsut getting to be too much for the ICM

 

It was sucking the paper back in at the tail pipe. Opti has about 35K on the rebuild. I found the EGR it was very dirty ( thought it was on the pass side???)

Coil is off the head with the washers mod.