Ok hoping someone has had a similar issue or just really knows Z's. I seems to be having a problem while under slight acceleration with the car feeling like its misfiring. Like a real quick jolt it doesn't seem to happen until my car is driven for about 20 min and is worse if I'm travelling up hill. Also without waring the car up I have zero acceleration or power. I'm not sure if it coencidd with the tempurature cooling down or something else. I have checked plugs, compession, timing and fuel pressure. Everything seems good. Just changed fluids too. Hoping to figure it out. Also it seems to be worse at around 1500-2200 rpm than anywhere else. No problems at idle other than fluctuations of idle rpm betweeen 800-1200 between stops just sitting idle bounces about 100rpm. Under full accel I haven't notices problems and at highway speed only notice it once in a great while.

 

So I'm to guess either no one cares or more likely I've come up with a problem that stumps even the best of us. I believe (know) that my problms only occur under power so I can run all the tests I like sitting in the garage. Everything seems fine even when giving my baby gas revving the engine everything seems fine. electronics seem fine, gas seems fine, no bad vacuum lines, fluids all good, no leaks, straight head, but under power going straight at low rpm or up hill at any rpm it feels almost like I'm running out of gas. No my fuel pump has been whining a bit lately. I don't want to guess at replacing parts.

 

Zero acceleration or power. What does your tach say? Is it like your engine is just shut off?

 

N e e d m o a r i n f o . . .

So all 6 spark plug tips are gapped correctly? All 6 tips look EXACTLY the same?
What is the compression across the board?
What is the timing at?
What is the fuel pressure at?

Have you checked the AFM? CHTS? O2 sensor? All connections? All grounds? All vacuum lines / ports? How old are: Cap and rotor? Spark plug wires? Ignitor?

 

@ThaPimpShrimp its not zero power really but it takes several seconds about 10 to go from 25 to 50 but thats only for the first 5 minutes of driving. my other problem doesn;t kick in till about 15-20 minutes of driving basically after its warmed up to operating temp.

@NismoPick Spark plugs are new (roughly 5k miles) When i pulled them out I did check the gap and they are propperly gapped to 0.040. Timing is set to 10 degrees. I did not write down my compression but I had my fsm with me and they were within specs. But i did it shortly after running the engine and if my piston rings are worn could have pushed oil up past them but my plugs were clean when i checked them so I'm suspecting thats not the case. But not impossible. I'll check again in the morning and write them down. Fuel pressure was 30psi at idle and 37psi revving. when i replaced the plugs I did a minor tune-up and cleaned and checked AFM at the time. though its possible its out of sorts. I did no check CHTS. I have a non-catalytic car there is no O2 sensor on my vehicle. all i checked when i bought the car all my electrical connections and used dieletric grease to prevent corrosion. When it was purchased i also checked my grounds and they still seem to be free of corrosion but I will again check those. When i started having this problem I cleaned out my vacuum lines figuring they were the culprit plus it never hurts. I'm not sure how old the cap and rotor are. They look newer and I have pulled the cap and cleaned the contacts. I also pulled the fuel rails and injectors placed 5 ft of fule hose to connect it back up. places injectors in mason jars and tested cone. all 6 sprayed well. spark plug wires were replaced at the same time the plugs were though its not unheard of that one is bad out of the box or was damaged so I will test those in the morning as well. Ignitor is new and tested within specks.

I did think of something else from reading my own post that I'm not sure why I didn't think about till now. It has been getting colder and that seems to be when it started going wonky though they could be unrelated it is possible that my cold start valve is leaking another thing i will check tomorrow. Looks like I'm going to have a busy day tomorrow. I hope i can get this all done before it gets dark.

Thanks for your help. I'll report back on what i find.