Dear Friends,

I am a Turkish student in Kansas and owned this car 2 months ago.I know these cars are very strong and long lasting. This one has a B23F 230.000 miles on it and has a pretty good shape.

Problem:Power loss,the car hardly reaches 70 mph and loses power at very low hills.

What I did until now: 1) My compression values are 195,200,210,205 psi

2) I cleaned the throttle body unit and replaced

the gasket.

3) I replaced the distr.cap,rotor and spark plugs.

4) Adjusted my timing 12 degrees and idle 700 rpm.

5) Fuel filter and air filter is also new.

6) I fixed all the vacuum leaks,it is 20 now.

***After all these stuff I just a got a little bit better idle.I still have power loss.

What I am planning to do is to Check the valve clearences.Am I on the right track?

My questions : 1)Is my compression too high,Haynes manuel says it should be

between 126-150

2)If it is high what can be the reason?

3)I am suspicious about my head gasket,does it cause power

loss,do I need to adjust my valve clearences again if I

replace my head gasket?

4)I know these cars have 2 fuel pumps,one is next to fuel

filter and the other in the tank.In my fuse box there is

only one red cable connected to my prepump(intank pump).

When I took the fuse out nothing is changing.The car

starts and drives.When I took the main pump fuse out the

car again starts and drives.Isn't it something wrong?

I am very sorry for my english and wish you a good luck to all

SHIFO

Hi everybody,

There is something interesting going in my car but I couldn't figured out yet.

First I put the hose in the tank and listened for the pump,sounds like it is working.Even if I pull out fuse 5,7!!!.Then checked the voltage, it is

fine 13,2 volts.I followed the red cable coming to fuse #7.It is coming from the junction box but going no where.Only one cable is attached to fuse#7 and I think there is something wrong with this.I looked at the electric diagram it shows a red cable coming from the junction box and going through fuel pump relay.I've checked both relays they are fine and working.The old owner told me that he changed cable harness they might connected some of them wrong and I really don't know what else to do but I appreciate your interest.

Shifo

Shifo:

Your English is pretty good. I see a lot worse from some Americans on here! Anyway, I don't believe anyone has mentioned yet that the in-tank fuel pump is connected to a very short length of rubber "accordion-like" hose before it reaches the metal line that runs out of the fuel tank. This piece of rubber hose can deteriorate and cause problems such as those you describe.

Good advice from the others regarding checking the ground wire and for voltage in the power wire at the top of the fuel tank. Bad grounds lead to all sorts of problems with the fuel injection systems in these cars (and their sensors).

The test I like to use to check the in-tank pump is to run the fuel tank down to less than 1/4 full, then with the engine off, disconnect the fuel line that comes from the tank at the rear of the main fuel pump (under the car, left side, simple hose clamp). At the fuse panel, connect a jumper wire from the in-tank fuel pump terminal (fuse #4, I believe) to #13, or another terminal that gets power when the key is turned to "on". Aim the fuel line hose into a gasoline-safe container and have an assistant switch the key to "on" but do not start the car. The in-tank pump should come on, and you should get a good strong stream of fuel from the hose. If you don't, but you hear the pump running inside the tank, the accordion hose is bad. If you don't hear anything at all, the in-tank pump itself is bad. There should be some information regarding the replacement procedure for these pumps in the archives. Good luck.

You asked me to stop by and look at your note. Good thing you did, as I mostly look at 700/900 posts.

I remember years ago finding a voltage drop to the pumps on a 240 like yours that was driving everyone crazy. I traced it to a real crappy fuse setup that allowed a lot of resistance. Low voltage = low pump speed = low volume. This will not show up as low pressure until the engine's demand exceeds the pump's ability to deliver.

The final fix was to cut the wires to the main pump fuse (under the block) and replace it with an external holder and a glass fuse.

Run the car for a while and feel the main pump fuse for heat. Anything more than slightly warm and you've found a voltage drop (resistance).

I've never owned a 200 car so I cannot tell you which fuse or what years had this problem, but I am sure that someone more knowledgeable on 200s will chime right in behind me and fill in the blanks.

Your slightly high compression readings are either from an inaccurate gauge (was it made in China?) or some carbon deposits. If you don't have to feed it super premium to keep it from pinging its guts out, then this is not a problem at all.

Other places to look for power loss (not quite sure why you think you have a fuel delivery problem from what you said):

Late valve timing - check that the camshaft sprocket is DIRECTLY in line with the cover mark while the crankshaft is stopped at TDC. Ignition timing has no bearing on valve timing so one can be right with the other wrong.

Incorrect timing procedure - your car might be one of those running manifold vacuum to the distributor advance. In that case the hose MUST be removed from the diaphragm to check/set ignition timing or it WILL be wrong.

My pressure gauge is an American brand,an older one which you just push by hand in the spark plug hole.

I did my timing BTDC 12 degrees vacuum connected as it was told in the owners manual.I do not have a vacuum connection on my distributor.

Anyway I am very happy to get a lot of replies from you.I'll try all your suggestions this weekend and inform you about the results.

Shifo

Definatly check the operation of your in tank pump,a faulty one can cause the symptoms you describe.(power loss at high speeds and when under load.)

Thanks Brian,

Do you have any idea how I can check that pre-pump in the tank.Is it easy to replace?

Shifo

Yes,you can check to see if the pump is running by having an assistant listen at the fuel filler neck( with the cap off) while you jump terminals 5 and 7 in the fuse box this will activate the fuel pumps and you should hear a humming sound from the filler neck.If don't hear the humming proccedto check the ground at the top of the in tank unit.If it is corroded clean it off and again check for operation.Also check the lead wire to the in tank pump for 12v.If you have 12v and a clean ground but still no humming from the filler neck the pump is in need of replacement.To replace the pump remove the panel to access the top of the tank.You then will need to turn the locking ring at the top of the in tank unit counter -clockwise (I've heard a short handled garden hoe works well for this task.)to release it.You then can pull the whole works upward and out of the tank.From there it is fairly strait-forward,just be sure to exercise extreme caution when working with the tank open, even the smallest spark could spell disaster.

You can check by running the car and listening to the pump. Try putting a plastic hose down the fuel filler tube a little ways, and you should hear it whirring. Also, many times when the pre-pump fails, the main fuel pump will make a louder noise than usual. This can eventually make this pump fail as well.

Replacement is not that difficult, you can do it from inside the wagon. You lift up the floor panel between the 2nd seat and the 3rd seat well. You will see the top of the fuel tank, and the place where the hoses and wires go in and out, this is the top of the pre-pump & fuel level sender assembly. It can be an awkward job, because the floor panel can get in the way, and the assembly will probably have a lot of rust around it.

To remove the assembly, use lots of penetrating oil, and you have to unscrew it by hitting it with a screwdriver and hammer, or with some special tool.

Maybe you also want to check your fuel pressure, and make sure your fuel pressure regulator is ok. That can make some problems, too.

Hope this helps.

Greg

If this intank pump fails will it also allow the car to vapor lock on arm days?

I think vapor lock is usually caused by a failing check valve, and probably not related to the intank pump. There is a check valve somewhere, I think it is somewhere near the main fuel pump, on the output side of the pump. When the valve fails, then it can let fuel pressure drop when your car is off. I think the fuel pressure regulator can also cause difficult starting problems.

Hope this helps,

Greg