Just finished replacing the head and all timing components and now engine is running very rough. It idles rough and hesitates during acceleration. Exhaust is making a put, putt, putt sound. Computer is throwing the following code:
P0134- O2 Circuit No Activity Detected (Bank 1, Sensor 1)
Would the lack of activity from the O2 sensor cause the problems I'm encountering?
Sounds like you didn't plug the upstream sensor back in....yes it could cause something similar to what you are describing.
The sensor not being plugged in will not cause what you are describing. The sounds you are describing should like bent valves.
FU Tuning
The reason the head was removed was because of bent valves. Jumped time and bent all 8 intake valves. I took the head to a machine shop which replaced the bent intake valves, ground the exhaust valves, cleaned everything up, and resurfaced the deck.
I just finished putting all back together last night - I had also replaced all the timing components (chain, tensioner, guides, and sprockets) in hopes of not bending valves again. When I manually turned over the crank, I felt no resistance and I'm pretty sure the timing is right on.
When driving home from the garage last night (first time driving since rebuild), I didn't have this problem (only a possible very random misfire maybe every 5 minutes or so). This morning I drove the car to work and this is when I noticed the latest symptoms. Co-worker has a scanner which gave me the P0134 code I'm investigating.
Still thinking bent valves? THAT WOULD REALLY SUCK!!!
Are you sure that first O2 sensor is plugged in/not bad?
That code can be tricky. I know for a fact that on the 3100/3400 motors, it can also be related to a clogged injector problem. I know that sounds crazy, but it's true. It also might relate to your random misfire. Double check your ignition system and run some fuel injector cleaner through your tank after you make sure the O2 is operating correctly.
My cousin is throwing that code (currently) and I replaced both sensors last summer; it didn't make the code go away.
bradford wrote:The reason the head was removed was because of bent valves. Jumped time and bent all 8 intake valves. I took the head to a machine shop which replaced the bent intake valves, ground the exhaust valves, cleaned everything up, and resurfaced the deck.
I just finished putting all back together last night - I had also replaced all the timing components (chain, tensioner, guides, and sprockets) in hopes of not bending valves again. When I manually turned over the crank, I felt no resistance and I'm pretty sure the timing is right on.
When driving home from the garage last night (first time driving since rebuild), I didn't have this problem (only a possible very random misfire maybe every 5 minutes or so). This morning I drove the car to work and this is when I noticed the latest symptoms. Co-worker has a scanner which gave me the P0134 code I'm investigating.
Still thinking bent valves? THAT WOULD REALLY SUCK!!!
I would hope not. Get the O2 sensor plugged in,but I have ran without one and the car will run fine. It could also be the vaccum hose on the map sensor. Check it for cracks.
FU Tuning
I'm almost 100% positive that the O2 sensor is plugged in, however, I do remember snagging the electrical connector on the oil dipstick when installing the exhaust manifold. I kept wondering why I was fighting to get the manifold lined up to the head until I noticed the connector was snagged! LOL I probably damaged the wiring when that happened.
I'm going to ATTEMPT to replace the sensor tonight and see what happens. I've got 200k on this car, so I should have just replaced the sensor when I had the manifold off - it would have been much easier. How difficult is it to remove an O2 sensor on a 2.4?
I'm really hoping that this solves my problem. So much money and time already into the valve job!
Okay... the wiring to the O2 sensor is now repaired and the P0134 code has cleared. The rough running problem, however, has not been resolved.
Now I am getting a P0302 (cylinder 2 misfire). The CEL is flashing and the cooling fan is constantly running. The plugs are new (AC Delco Double Platinum), boots are new, and the resistance on each of the secondary terminals of the coils is approx 5640 ohms.
Any ideas?
Latest information on cyl 2 misfire....
Pulled #2 spark plug which was dry, but the cylinder appeared to be wet and there's a strong smell of gas. I also swapped the locations of the two coil packs and still get the misfire on #2.
What should I check next?
Is #2 fouled out? Is it working? Might wanna throw some new plugs in just to make sure
I would try another set of plugs, but I'm think the coil housing is shot.
FU Tuning
I'm planning on doing a compression check tomorrow. If the compression checks out, I'll probably try a new coil housing.
How does one go about checking for spark on the 2.4? I'm not sure because of the 2.4 setup.
Thanks for all the input so far!
Take coil cover off, attach to spark plugs via spark plug wires, use inline tester.
Problem is solved and car is running GREAT! Sometimes we neglect to check the most obvious!
How in the heck did I break the insulator on this plug and how the heck did I not notice this sooner?
Oh well... that's how we learn! Thanks all for suggestions!
what insulator are you talking about? I don't see any picture and my car is doing the same damn thing.
Equipt with Replacement for Displacement components
Dragracemyz24 wrote:what insulator are you talking about? I don't see any picture and my car is doing the same damn thing.
I think he's referring to the ceramic insulator built into the spark plug itself.
YES... The ceramic insulator on the plug was busted and the plug was sparking, but between the side of the plug and the head instead of at the tip of the plug inside the cylinder.
What I learned from this is "always check the spark plugs first," even if they are brand new. What I thought was a major problem turned out to be the most simple solution.
Good luck Dragracemyz24.
Not sure why the link to the pic isn't working. It's not a great pic anyway.
I'll try posting it again.
