86 Running VERY ROUGH hard to start and will not idle LOW power

[scenario]

My 86 out of nowhere started running rough a few weeks ago. I found the TPS plug was unplugged (on its own...go figure). That fixed it, now I go to start it the other day and it is acting the same way so I figure the plug worked itself out again but that is not the case.
Honestly, I think it is running on 3 cylinders bc it is so rough and has no power.

I dont even know where to start. Jeez... I can barely start it to get it running and I want to get it in the garage to start troubleshooting. I think I am goint to pull the intercooler and check compression.

I can not check timing bc it will not stay running without feathering the gas pedal. I dont think it is the TPS bc its running so horrible. Exhaust is not horrible as if a blown headgasket but it just may be that...

I did change the valve stem seals like a few hundred miles ago and maybe something in the rockers popped out??? I dont know

Any input would be greatly appreciated

FV

[cookin86]

Seems like mechanical failure would be really noisy. Head gasket would not only likely puff white smoke, but result in milky oil, high temps (if you keep it running long enough) etc. Check, plugs, wires, fuel pressure, vacuum leaks. The way you describe it must be something obvious.

[scenario]

I just did a compression check and I get
cyl #1 = 25psi
cyl #2 =25psi
cyl #3=130psi
cyl #4=140psi

I guess its DEEP....oh well, like I always say "dont threaten me with a good time!"... (I just say thast to motivate myself when I gotta start tearing things down...

I will update


A testament to the Ford 2.3L engine that I actually got it running on "2" cylinders to get it in the garage....

[svono50]

Bummer, but at least it was a somewhat 'obvious' failure with those numbers. Our little 2.3's are pretty durable as I have been driving various versions for the past 38 years. A former NA 2.3L I had in an 80 Mustang had slipped its timing belt 7 teeth and it still got me home...but felt down on power...go figure! New belt, reset timing and good as gold...easy, peasy...

[scenario]

OK
I set #1 cylinder to TDC exhaust and intake valves are CLOSED. I pressurize cylinder #1 and air is flowing into cylinder #2 out the spark plug hole. Head MUST come off. It has to be a complete tear in the head gasket between #1 and #2.

Starting to remove the head now. I am more talking out loud on this than anything else but if any input please feel free...

Oil is clean and antifreeze is clean so IDK I would have expected differently and now real bad white smoke to speak of either out the exhaust BUT this did not happen when the engine was at operating temperature so maybe that is why and I quickly got back in driveway when it happened...

[scenario]

Here it is between cyl #1 and #2

[svono50]

Yep, that is not and uncommon spot for our gaskets to fail. Usually see it between cylinders 2 & 3, but no reason it can't happen there too. Fortunately it avoids mixing coolant/oil, but still a pain in the rump to deal with.

While things are apart, you may want to send out your injectors for a cleaning/check/balance if you haven't before. One of the cylinders could have run lean as one of many potential causes of the failure.

[cookin86]

Ouch. That's about all i can say.

[Bruce]

Been there and done that! For me it's a weekend job now. AS long as everything is flat.

[scenario]

Head and block seem OK. I ran a straight edge across both and seem to be true. I did not notice any area that a feeler gauge would have snuck under. This was NOT due to an overheat so hopefully will be OK.
Good idea on the injectors. I just need to find a place on Long Island or somewhere to send them out to.

That damn intake manifold is a real BEAR to get out...going back in is gonna be worse I think...that stupid bottom bolt in the middle will suck and prob cost me some skin....smh

The bolts under the bracket for the intercooler mount on exhaust manifold is not much better...miracle it came off...

[gbeaird]

Been there and done that! For me it's a weekend job now. AS long as everything is flat.

Same here! We let someone drive our 86 at an autocross, and he brought it in missing. I think the blowout was between 3 and 4, but same thing. Pretty easy fix, as far as head gaskets are concerned. Getting the timing marks on the cam and crank gear was the hardest part of the whole thing, other than muscling the head out of the way, and back on.

IMHO, taking the intake/head/exhaust manifold out as a unit was NOT the easy way to do it. intake and head, maybe, but unbolt the exhaust manifold from the head.

[scenario]

Same here! We let someone drive our 86 at an autocross, and he brought it in missing. I think the blowout was between 3 and 4, but same thing. Pretty easy fix, as far as head gaskets are concerned. Getting the timing marks on the cam and crank gear was the hardest part of the whole thing, other than muscling the head out of the way, and back on.

IMHO, taking the intake/head/exhaust manifold out as a unit was NOT the easy way to do it. intake and head, maybe, but unbolt the exhaust manifold from the head.

I didnt even think of taking it out as a unit. I guess I was overwhelmed with all the things I couldnt see and just took things apart as I went along. Leaving the intake would have been advantageous for the sake of the underneath bolts...maybe in my next life...

Almost done now.

I marked the timing belt and the pulleys before I disassembled and reassembled identical. I started with #1 at TDC. I spun it a few rotations and eveything seems to be ON as far as timing goes but will have to wait till I actual start cranking it

[scenario]

Thankfully, I got it all back together (no bolts or parts left over... )

She started up on the first turn of the key. Idles right down and drove pretty good. I cleaned out the throttle body and intake manifold and polished inside a little bit. Took out some casting burrs as well. Hopefully she is happy and will keep on going

[svono50]

Great news. I have always pulled the head with the exhaust manifold/turbo on it, because it can be a pain to get them off/on, but have always pulled the intake manifold. There is a combination of universal joints and extensions that get your hands out in a semi-clear area to loosen/tighten the lower screws. The top screws are all easy, so long as you pull the upper manifold off.