Random misfire at idle 454 vortec

[elevatorman]

New member here and ive got a 97 k3500 454 vortec that has got me stumped i bought the truck about 2 months ago had a very bad idle found the cap was missing a screw fixed that and truck ran hardly any better...
Since then ive found a bad fpr leaking injector replaced with bosch didnt help the idle
Fuel pressure was only getting too 46lb replaced the pump now up to 51 at prime and 47 at idle.
Replaced plugs and wires and after 2 days of running the truck a few were oil fould and fuel trims 25% after **** smoke test observed smoke out of dipstick tube so i replaced the intake gaskets fuel trims did come down some and idles slightly better.
Truck has true duals and ive reomved the cats due too being booger welded in and 2 different sizes.
I recently found 15 degrees of slack in timing chain by watching the rotor so i just replaced the timing chain and sprockets.
Still no change lt bank 1 trim 17% bank 2 10% it has a misfire on cylinder 1 in park at idle tmits not constant if i drop in gear foot on brake misfire moves too 6 of 8 cylinders and gets more frequent i know this has too be the cause of my high fuel trims but im stumped distributor has been inspected no play in bushing gear is good cam retard is 0degrees at 1200 rpm.
Im using a tech 2 tool all sensors are working. Truck has never thrown a code except for post 02 heaters. Also truck runs very well cruising fuel trims fall back too normal. Grounds have been cleaned and some replaced.
Compression 150ish all cylinders. Also does not smoke

 

[Scooterwrench]

Did you replace cap and rotor?

 

[elevatorman]

Yes that being said i used ac delco. But ive found someone already changed the distributor too a no name

 

[Scooterwrench]

OK,so the only issue is at idle? Check EGR and IAC.

 

[elevatorman]

Yes idle is the issue.
Egr position at idle 0% and desired position is 0%.
Iac bounces between 2 and 0 counts when hot which i believe is due too the miss leaning itself out

 

[Keeper]

that's fairly low fuel pressure for a vortec isn't it? aren't we looking for 60+

 

[elevatorman]

Ive read mixed reviews on that i would prefer more but thats the most i can get fpr not leaking and new pump

 

[Schurkey]

97 k3500 454

Replaced plugs and wires and after 2 days of running the truck a few were oil fould

That's gotta get tracked-down and fixed. Valve stem seals? Wiped valve guides? Faulty rings? Sucking oil via PCV or intake gasket leak?

i replaced the intake gaskets fuel trims did come down some and idles slightly better.

Does it still foul plugs, or is that problem FIXED?

I recently found 15 degrees of slack in timing chain by watching the rotor so i just replaced the timing chain and sprockets.

Did you degree the cam, or just cram the parts together "dot-to-dot"?

Did you retest for slack by watching the rotor the same way you did before replacing the timing set?

Still no change lt bank 1 trim 17% bank 2 10% it has a misfire on cylinder 1 in park at idle tmits not constant if i drop in gear foot on brake misfire moves too 6 of 8 cylinders and gets more frequent i know this has too be the cause of my high fuel trims but im stumped distributor has been inspected no play in bushing gear is good cam retard is 0degrees at 1200 rpm.

Punctuation, capitalization, and sentence structure were taught in elementary school. This is more of a paragraph, not a sentence.

OK,so the only issue is at idle? Check EGR and IAC.

Yes.

Egr position at idle 0% and desired position is 0%.

Doesn't mean it's not leaking.

Iac bounces between 2 and 0 counts when hot which i believe is due too the miss leaning itself out

Seems low.

 

[454cid]

that's fairly low fuel pressure for a vortec isn't it? aren't we looking for 60+

Small Blocks need the really high pressure. My 454 is a bit lower too. His still might be a bit low, but I would not expect that to be the cause at idle. I also have a misfire that I can hear/feel, but not the PCM. I am going to compare my plug wire routing to the manual, so as to be sure I'm not getting wires inducing spark to each other. I've also got an EVAP solenoid that I think is leaking, which would amount to a vacuum leak, If I understand it's operation correctly.

This should be an interesting thread to follow.

 

[elevatorman]

That's gotta get tracked-down and fixed. Valve stem seals? Wiped valve guides? Faulty rings? Sucking oil via PCV or intake gasket leak?


Does it still foul plugs, or is that problem FIXED?


Did you degree the cam, or just cram the parts together "dot-to-dot"?

Did you retest for slack by watching the rotor the same way you did before replacing the timing set?


Punctuation, capitalization, and sentence structure were taught in elementary school. This is more of a paragraph, not a sentence.


Yes.


Doesn't mean it's not leaking.


Seems low.

Unsure if oil fouling has stopped ive got too pull plugs again. Ive already replaced intake gasket due to it pulling from crankcase.
As far as degreeing the cam im not sure what you mean i rotated the old set too tdc with dots aligned and installed new set dot too dot no more excessive slack did not check the rotor.
I apologise if my punctuation and writing bothers you im not much on writing