Misfire and no power....

[Kraig]

Also, I just went back and read through and noticed you asked about checking exhaust port temps with the engine warmed up or no. If the engine is warmed up, the manifold can heat soak. You want to check it cold. Each port should heat up at about the same rate. If you have one that doesn’t get warm until the engine is warmed up and heat has soaked into the manifold, that could be a sign.

 

[sgosa]

Also, I just went back and read through and noticed you asked about checking exhaust port temps with the engine warmed up or no. If the engine is warmed up, the manifold can heat soak. You want to check it cold. Each port should heat up at about the same rate. If you have one that doesn’t get warm until the engine is warmed up and heat has soaked into the manifold, that could be a sign.

I’ll recheck them. I was wondering if the heat soak would be an issue.

 

[sgosa]

Cold cyl temps
Driver side rear 96
2nd from rear 115
3rd from rear 158
Front 128

Passenger side
Rear 106
2nd from rear 128
3rd from rear 108
Front 138

 

[Scottydoggs]

pass side, front to back, 2,4,6,8

driver side, front to back, 1,3,5,7

thats how the cylinders are numbered. just so we can talk with no confusion.

#8 seems pretty cold. you just getting multiple misfire code? po300, or you getting cylinder codes too?

could also be a bad injector not giving that cylinder any fuel.

 

[Tonyrodz]

yes, or bad coil pack, try swapping coil packs around see if you get the same or different results, I know you said you checked them but wouldn't hurt to confirm, you can get the "herko" injectors off of ebay very very reasonable, they are essentially oem I believe they are made in the same plant I have bought a couple complete sets and had excellent results, just get the ones with 4 nozzles as those are the flex fuel ones.

**you may want to check the voltage on the harness connector to the suspect injectors as well to verify they are getting power

How much are those injectors? Have a link?

 

[sgosa]

I think I saw 1A Auto had a full set for $160 or so.

 

[sgosa]

pass side, front to back, 2,4,6,8

driver side, front to back, 1,3,5,7

thats how the cylinders are numbered. just so we can talk with no confusion.

#8 seems pretty cold. you just getting multiple misfire code? po300, or you getting cylinder codes too?

could also be a bad injector not giving that cylinder any fuel.

Just random misfire code. And was getting the mass air flow sensor code. Replaced it, now just the P0300.

 

[sgosa]

Another newbie question. If it turns out to be the cats are clogged. Can I do dual exhaust and eliminate the Cats altogether? Or is this newer stuff not suitable for that?

 

[Scottydoggs]

you will likely need to tune the cat code out if you delete the cats. that means a tuned pcm.

 

[sgosa]

I threw in the towel today guys, and took it to a local shop. Hopefully I might hear something tomorrow. Thanks for all the info!

 

[89Suburban]

I threw in the towel today guys, and took it to a local shop. Hopefully I might hear something tomorrow. Thanks for all the info!

 

[Servando]

Any luck?

 

[sgosa]

Not yet. The shop I took it to has not impressed me so far. He’s had it since last week and hasn’t really done anything. If he doesn’t at least have some sort of diagnosis by tomorrow afternoon I guess I’ll take it somewhere else.

 

[JetBlackNali]

Sounds like a lead is grounding out or a coil pack is cracked and grounding.

Had my son (14) help me do plugs and a set of leads a while back. Delco plugs and msd wires. Ran great. He was happy to help dad in the garage, and I was happy to share with him.
Leaving work one night fire the truck and it's chugging, popping, barely rev, cel is on. Frack. Throw the scanner on random misfire. Hmm. Pop the hood get out of truck it goes away. Wtf. Get back in starts again . Going crazy now. Is my seat hooked up to the ignition?

Get a buddy to sit in truck. Nothing. My truck hates me. Great. So with him sitting in truck and me under hood with a flashlight in my teeth, start feeling around . Nothing. So now I'm looking for a hammer. So buddy gets out and I hear it, Crack ,Crack ,Crack of the spark. Gotcha Fracker.

Turns out when I was getting out I was moving the steering wheel and the steering shaft bolt at the bottom of the column was digging into the #5 (2nd from back driver side) cylinder lead. Thank the good man above it was dark out and I could see the spark jump.

So my fix to get home was a piece of airline cut lengthwise and tie straps.

 

[Tonyrodz]

Sounds like a lead is grounding out or a coil pack is cracked and grounding.

Had my son (14) help me do plugs and a set of leads a while back. Delco plugs and msd wires. Ran great. He was happy to help dad in the garage, and I was happy to share with him.
Leaving work one night fire the truck and it's chugging, popping, barely rev, cel is on. Frack. Throw the scanner on random misfire. Hmm. Pop the hood get out of truck it goes away. Wtf. Get back in starts again . Going crazy now. Is my seat hooked up to the ignition?

Get a buddy to sit in truck. Nothing. My truck hates me. Great. So with him sitting in truck and me under hood with a flashlight in my teeth, start feeling around . Nothing. So now I'm looking for a hammer. So buddy gets out and I hear it, Crack ,Crack ,Crack of the spark. Gotcha Fracker.

Turns out when I was getting out I was moving the steering wheel and the steering shaft bolt at the bottom of the column was digging into the #5 (2nd from back driver side) cylinder lead. Thank the good man above it was dark out and I could see the spark jump.

So my fix to get home was a piece of airline cut lengthwise and tie straps.

View attachment 222394

I think that's a super common issue with aftermarket wires due to the longer length. I had to zip tie mine away from that shaft bolt too.

 

[sgosa]

Wow. That sounds like my luck man!
We found part of my issue. Cats are definitely clogged up. Once that’s resolved we’ll see if anything else is causing problems.

 

[Tonyrodz]

Wow. That sounds like my luck man!
We found part of my issue. Cats are definitely clogged up. Once that’s resolved we’ll see if anything else is causing problems.

Gonna cut them out or hollow them out?

 

[JetBlackNali]

I always use Walker hi flow universals. They are cheap and flow really well.

 

[Rocket Man]

Clogged cats did about the exact same thing to me, with those codes and more. I’m pretty sure that will fix your problem.

 

[sgosa]

Cutting them out for now to get going. I’d like to a new system this summer. But not quite ready yet.