more convert problems

Stableboy

Founding Member
Nov 29, 2001
93
0
6
Perryville MD
I need some educated opinions please. My wife got me a 1990 convert for a gift. the seller said it needed new plug wires. It runs like junk and cannot get above 65 and cant hold spped either going up hills. I ran a compression test and the 2 cylinder holds 1/3 the pressure of the other 3. There is no oil in the coolant, no gas in the oil and no collant in the oil. I have been informed that it is most likely bad valve seats or a wiped lobe on the cam. The car does not blow that much smoke, the plug had gas on it but not oil. If it does need head work, is it more cost efficient to put in another motor? Also can a Ranger motor mount up without modifying sensors or anything?
 
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Low compression can be cause by a few things: worn piston rings, a damaged/burnt valve, or bad valve seals. In your case, being that it is isolated to 1 cylinder, I would almost suspect a burnt valve or bad cam lobe. Easy thing to check: remove the valve cover and inspect the exhaust or intake lobes for that cylinder. If it is excessively damaged, that would be your problem. As for a Ranger engine, I would imagine any 85-88 (NON mass-air) engine would fit without much modifications. The easiest thing would be to remove the head and have it rebuilt. I had mine done at NAPA for $189 bucks total including tax. Of couse gaskets are extra, but they don't cost that much. I did the whole thing myself in a few evenings in my garage. Dumb question, but did you do a tune up (plugs, wires, rotor, cap) on it? My 88 had a horrendus misfire and little power above 55mph but a tune up fixed that.
 
I would pull the codes and see what they say. even if the CEL is not on there is most likely some stored in the computer and they may point you in the right direction. If you are going to replace the motor I would just go with a 2.3 turbo. it drops in with minimal modification and has twice the ponies of your stock motor. the easiest thing to do would just get another head from a jy and drop it on. just my .02
 
My buddy and I did a tune up, cap, rotor, new plugs/wires oil change. Car ran a little better, but still has rough idle from bad cylinder. after still running rough we did compression test, that is when #2 popped up as poor compression. I would like to keep the car basic, I allready had a turbo, 84 svo, i just want something to run around in
 
I agree, get a junkyard head and have it rebuilt. Put a new cam in too. Does that cylinder burn a lot of oil? (what did the old spark plug look like?) If it is limited to 1 cylinder, I would say its a valvetrain issue and not a piston issue. Could even be a leaking head gasket.
 
the old plug and the new one after a few miles smelled like gas. Are there other type of heads i could ask for when calling junkyards. I know the later cars had the 8 plugs, did that start in 1991 or 1992? I know my 1993 had it. When you say 185 at napa, was that for all the parts to go onto a junkyard head, or was that to have your present head reworked to usable condition?
 
Yea, 8 plug heads are out. Basically, you can use any non-turbo head from a 1982-1990 2.3L (except for the Ranger, which began getting an 8 plug head in 1988 I believe.). Earlier heads have oval intake ports, yours would have D shaped ports. The 185 bucks at NAPA was having a complete (without cam, followers, and lifters) 1989 Mustang head magnafluxed, cleaned, new valve seals installed, valves ground, new expansion plugs installed, new cam bearings installed, new cam oil seal installed, and checked for squareness. If in fact you would need new valves, they would cost about 15 bucks each. If the plug smelled of gas, that would almost seem like an ignition problem (it's not burning the fuel entering the cylinder), but with low compression, it could indicate a chewed cam lobe, damaged valve, or leaking head gasket. Being that the block and head are cast iron, I would think they would be ok and not the cause. If you can tinker with this car, I would consider first just removing the head (it's not near as hard as it looks). If the head gasket is blown or leaking, you'll probably see it. It will come apart a little bit when lifting it off. Flip the head over and visually inspect the valves. A burnt valve will be discolored. You won't be able to see microscopic cracks or damage, but sometimes just taking a good look and working the cam by hand and watching the valves can reveal the issue. While the head is off, take a look at the pistions and cylinder walls for damage, discoloration, and scoring/scratching on the cylinder walls. Regardless if you can see a problem or not, it would probably good to have the head rebuilt. I chose NAPA because I used to work there and I know they do very good work at a good price. Of couse it will vary by area. If you know of any good engine builders or machine shops in your area, call them up and get a price. I couldn't forsee a FULL (new EVERYTHING) head rebuild costing more than 250 bucks.
 
The previous 2 people on the 2.3L board that you have put down simply because of their engine size have legit concerns. Unless you have something constructive to say, please leave the unnecessary comments aside. Some people on here may want 5.0L engines eventually, but don't you think it would be nice to at least drive and enjoy the vehicle until they do the swap? I have no plans of ever swapping a 5.0 into either of my cars. Why? I love the fuel economy and ease of repair. So, all I am saying here is that if you have valuable information to add to the thread, please do, it's what it's here for. But, if you're just going to beat up on a poor guy for the size of engine his car has, leave us alone.
 
Anyone have opinions on the idea that a fuel injector is stuck open, causeing the loss of compression due to the displacement of the oil by the gas? it would also cause the plug to smell like gas and cause the smell of raw fuel to come out of the tail pipe?
 
It's always possible, but it is really a rare thing to happen. I don't know if dispursal of the oil on the cylinder wall would create that much of a compression drop though. Does the oil smell like gasoline? Are you getting intermitten puffs of black smoke out the tailpipe? You may also get an "always rich code from the oxygen sensor, but that could be caused by a failed sensor too. If you're getting raw fuel out the tailpipe, you're definitly running waaaay rich.
 
sounds like that cylinder is not firing properly, did you check the plug wire on that cylinder to see if you are getting spark?

That would be my first step. Check for spark, if you are getting spark, then your second step would be to swap injectors from a good firing cylinder. If that doesn't work you can rule out both the injectors and the ignition spark.

This is strange, keep us posted and don't give up.

About that 5.0 guy, he is in the wrong forum. You want to fix your car and you have some joker who thinks he has a fast 5.0. Just because its a v8 and starts joking on how you are missing 4 cyl. Plain rude and uncalled for.

I am sure there are many 4 cyl that would whip his v8 on this forum. Plus he must love the gas prices and his v8 fuel economy. :nono:
 
OK...I took the head off after doing a 2nd set of dry/wet compression tests. My buddy, a ford tech at a Philly dealer supervised. We found the heater core was replaced at one point and the head gasket was blown. We also found a bent valve (I really couldn't see it, but he identified it.) He said that because the valve wasn't seating 100%, the compression of the cylindar was going around it. He put the valve in the closed position and pour some gas on it and the gas all leaked through. Hopefully this is the answer.
..About the rude guy.....if it wasn't for 4 and 6 cyl mustangs there would not have been 8 cyl through the 70's into the 80's. Lots of rental places buy Mustangs without 8 cyl and that flows back in to big blue. It is not a Ford, but I have seen my brother's 87 Turbo Regal wipe up a lot of Mustangs with 8cyl...
 
Sounds like you found the problem. A valve that is not seating will cause all the problems you are having. Replace at least that valve (if not all of them just to be safe) and have the head checked for damage. Once you've got everything back together, it should run like new.