Nelsontacoma
New member
So I'm seeking some advice on my 96 4runner. 3.4L Automatic 2wd. This is a long story, but the more details I give the less questions you'll have to ask. When I bought the truck 3 months ago it had a check engine light come on, code P0303, I found that the #3 spark plug was cross threaded and hadn't been changed in a while. No big deal, fixed the hole, replaced all the plugs and it runs great. So next I decide to replace the leaking oil pan gasket. Well, during that repair I find that I have coolant leaking inside the engine block from the #3 cylinder area. Figured it was time to do a head gasket job.
So I finally replaced the head gaskets. During this process I find the right side head is cracked between the valves in cyl #3 & #1. So I purchased a junkyard head to replace it. I rebuilt both heads myself, lapped all the valves & replaced the valve stem seals. I also sent all 6 fuel injectors out to get rebuilt since I had them out, figured now was the best time.
I finished putting the truck together today. Checked valve lash clearances all were good. Set timing and put everything back together. So after filling it with oil & coolant, I fire it up. It starts right up after no major issues, except for it idles rough. Drove it around and get a flashing check engine light with code P0305. Started with a compression test, all good. Ok, so I swap coil packs from #3 & #5, same code. Next I swap spark plugs #3 & #5, same code. I checked for vacuum leaks, didn't find any.
So what else could be the issue? Maybe the injector is bad? I didn't swap those, probably should try. Anyone else have any ideas? Thanks in advance.
I posted this on Tacomaworld to. Sorry to double post, but the more opinions I get the better.....
Compression test results.
Cyl 1 160
cyl 3 170
Cyl 5 178
cyl 2 190
cyl 4 180
cyl 6 180
So I finally replaced the head gaskets. During this process I find the right side head is cracked between the valves in cyl #3 & #1. So I purchased a junkyard head to replace it. I rebuilt both heads myself, lapped all the valves & replaced the valve stem seals. I also sent all 6 fuel injectors out to get rebuilt since I had them out, figured now was the best time.
I finished putting the truck together today. Checked valve lash clearances all were good. Set timing and put everything back together. So after filling it with oil & coolant, I fire it up. It starts right up after no major issues, except for it idles rough. Drove it around and get a flashing check engine light with code P0305. Started with a compression test, all good. Ok, so I swap coil packs from #3 & #5, same code. Next I swap spark plugs #3 & #5, same code. I checked for vacuum leaks, didn't find any.
So what else could be the issue? Maybe the injector is bad? I didn't swap those, probably should try. Anyone else have any ideas? Thanks in advance.
I posted this on Tacomaworld to. Sorry to double post, but the more opinions I get the better.....
Compression test results.
Cyl 1 160
cyl 3 170
Cyl 5 178
cyl 2 190
cyl 4 180
cyl 6 180