95 no power/accel tried several things

[warthogdriver]

sorry first post

ok some background info...sorry its long but i am trying to be thorough.

196,000 mi
3.8l 5 spd
i have only but about 1000 miles on this myself..owned for a year, first actually attempt at driving with it as daily driver

p.o.
said head gaskets and clutch were replace thats all in way of major maint.

i have replaced vac lines
did compression check (115 - 130ps) each cylinder held compression
new plugs are autolite and all came out dry and looking good
plug wires are new...autozone store brand
cold air intake
oil pressure is within range 60-90 while running at 2000-2500 rpm
oil pressure does not jump all over the place (aftermarket pressure gauge)
no loss of oil at all
runs at max 210 temp normally
antifreeze is green and not disappearing at all
exhaust doesnt smell at all...no smoke or discoloration if i hold white rag to exhaust
2.5" dia exhaust with high flow cats
fuel filter
seafoamed gas, oil (and changed) and intake
i held a long screwdriver to injectors and can feel all 6 tapping away.
have ran it with oil cap off and no smoke comes out of valve cover

no knocking or tapping of any sort

replaced:
tps and cam pos sensor....both had thrown codes.
tried cleaning maf sensor and iac

recommended by others:

i have harmonic balancer on way...engine has a bad vibration...can be felt in steering wheel and seats.

obvious problems i have:
only code is for o2 sensor bank 2
gas mileage is about 13 +/- mpg almost all city though

problems i am having:
no power from dead stop i have to rev up to 2000rpm just to crawl...once moving all seems fine. if i step on it from dead stop the engine does nothing.
idle drops to 500-1000 rpm at stop
when on highway in 5th i lose speed gradually
timing seems to be off some days....backfires out intake/exhaust

separate maybe:
and now i am overheating...i think i have an air pocket...just did t-stat.

i got the spark tester out and did the the coil pack...fired great on all 6 outputs. nice bluish purple spark on tester..a hint of yellow but mostly blue.
(dont know if the color matters or not)....i had the tester set above gap, i figured if it could jump more then gap then the power is there to fire the plugs.

i swapped in a diff iac...got one from a buddy, cant beat a freebie...no change.

i am going to take egr out and clean it ...see if that helps.
after that i am gonna take out injectors and clean them out, pressure test first of course.

i just hate wasting great summer driving weather on "hide and seek" issues.

ohhhh and i also stumbled across something weird...if i push pedal straight to floor real fast i get no response at all...but if i slowly push it and pump it a little the car will shoot up to 2000 rpm and away i go...real smooth like nothing is wrong at all. after that at idle i can pump pedal and i get a response immediately, but it will drop as soon as i let clutch out to drive. if i then shut the car off and wait a minute and fire it up it is back to dead response on pedal unless i slowly pump the pedal again to work it back up.
now i have replaced the tps...i had this dead response earlier so that was not it.

i know that throwing parts at a problem is the wrong way to do this but with 196k on the clock i figure it cant hurt here and there.

thank you...if you need any other info please ask

 

[wmburns]

What I think is happening is the car is over heating. As part of the failure mode effects, the PCM takes steps to protect the motor. One of the things the PCM does is to remove timing. This controls the heat that the motor produces. BUT it also reduces the power output of the motor.

SO.....how did your purge the air from the motor?

Check out:

1998 mustang irregular rpm's showing hot - Ford Mustang Forums

With regards to getting help for your other issues, those of us out in Internet land really need to know the full DTC codes. There are 1000's and each has a story to tell.

However, I really suspect that some of your issues will go away once the engine temperature is under control.

If there are still problems with poor throttle control, a couple things come to mind.

The compression seems low. What happens if a small amount of oil is added to the cylinder and the test repeated? A large increase in compression after adding oil could mean worn pistion rings.

Check for a blocked exhaust. Perhaps clogged cats.

 

[warthogdriver]

when i did the t-stat change i filled rad and ran with cap off...i did not fill thru the vent tube...i did have the bolt in the top loose. i figured it was so the air could be be pushed out by filing the system. i will revisit that, and do it right. thank you for the link.

as for codes i will rent the scanner again and get more details to report back.
good point on codes, hundreds of them with hundreds of reasons.

i did try running the car with the exhaust disconnected, no change there.

as far as increase in compression numbers, what should make me concerned?
either way i will report back as much info as i can get.

thank you for the help, i am at wits end with this....i will usually try to fix most things...i just don't know where to look this time.

 

[warthogdriver]

ok,
well good news is i got the air out of the cooling system.
bad news...i reran the compression test dry/wet and found the problem.
i have lost compression on the middle cylinder on drivers side and rear cylinder on driver side as well....so i guess i have to look at my options.
i know at best it is a valve job, at worst head gaskets.
i have no fluid cross contamination so i think block is sound. i just dont know what to put into this now.
i am thinking with 200k almost on the clock a rebuild is in order.
or i can go with a engine from local yards for around 600-700 with about 100k or so on them.
problem with yard engine is it could be a roll of the dice.

any opinions are welcome at this point.

i wanna say thanks for the help.
looks like i have a full plate to deal with now.

also any ideas on good rebuild kits?
i am not looking to build a 1/4 mile monster.
i just want a daily driver with some pep.

thanks again.