420A Hesitation/rough idle

[609DSM]

My idle is extremely rough when car is at temp. It goes from 950rpm and will drop down to 600 and as low as 500, does this when I come to a full stop at a light. Then it has trouble getting going, I have to really get on the gas to get the rpm to 1.5k to 2k for it to leave a stopped position.

I cant even go full throttle or what happens is it picks up speed then the torque just dropped and it revs a lot slower and gets a little quieter and all power it had comes to a halt, then randomly it kicks back in and has full power.

So I cleaned my intake and throttle body, replaced the MAP sensor and the throttle positioning sensor along with my broken coolant temp sensor. I've also checked for vacuum leaks as well and havent been able to find any from my inspections.

Could this be a fuel issue?

 

[609DSM]

Only evap when it checks it with the LDP. Since I removed the egr I get p0403 now

 

[609DSM]

STFT bounces between lean and rich at idle. LTFT is very lean, around 12-22 at idle. Same thing when my headers were basically cut in half from rust

 

[609DSM]

Also noticable change in exhaust sounds. I can hear it sputtering from underneath the passenger side where the cat is but cant visually see the leak. I'll Jack it up and check things out when I have the time. Life is getting the better of me right now...

 

[BLACK'98DSM]

Could just be as simple as a bad gasket, or some loose bolts

 

[609DSM]

Yeah, it's been all rainy after school lately so I'll have to let it sit for a couple days before I can check it out. I'm hoping it isnt anything crazy but I'm also ready for the worst....

 

[609DSM]

Just patched up my tire. Had a screw in it. Cylinders 1 and 4 are not firing, had started the car to diagnose what's going on. It's nearly impossible to start, have to play with the gas pedal. Didnt sound right, couldn't hear an exhaust leak like I thought (its cold as hell so could be a bad gasket). Went to look at the engine for leaks and coolant loss, nothing coming out of engine and no coolant loss. Touched the header pipes and 1 and 4 had no heat

 

[609DSM]

Not sure what the issue is without running voltage/continuity tests with my multimeter. I'm suspecting possible bad coil pack or wires. I did recently check the wires a couple thousand miles ago and their ohm reading was fine across the board

 

[BLACK'98DSM]

More likely the coil pack then

 

[609DSM]

Thats my educated guess as well. I'm test the coil pack tomorrow and grab a hopefully working one I've found at the pick and pull. Wires look brand new and pack looks replaced so it will serve its purpose while I can casually order brand new online when I have more money. Cash is super tight so before i even spend 20 at the junkyard I'm gonna run the coil pack test

 

[609DSM]

Fixed the issue. I believe it to be my own fault, I misunderstood the purpose and properties of dielectric silicone grease and applied it to the contact of the spark plugs. This resulted in insulating the spark from occurring and effectively shutting down cylinders 1 and 4 from combusting. Got a new coil pack and thicker spark plug wires for 20 bucks at the junkyard. Wires say DLG suppression wire, dunno what brand that is couldn't find anything on it. Gonna test drive it when I get back home but after installing everything with some new plugs it started right up and ran like a champ, minus the small vacuum leak I hear behind the intake.

I feel stupid but at least I learned something. I thought dielectric grease insulated from water/moisture and conducted electricity , lesson learned!