Diagnosis, anyone?

[ironheart1]

Ok, I admit it, its true. My GT has so many problems, its absurd. But here's the latest and the greatest... Any advice, tips, or feedback would be great. And by advice, I don't mean "sell the car" because I'm way too attached to her to do that.

We just did plugs/wires/cap/rotor/oil change/thermostat. FINALLY, having replaced everything in the cooling system except the radiator itself and everything in the starting/charging system save the starter solenoid, we thought we had it nailed down. It took a lot of troubleshooting and whatnot but we got it... But as we finished the last task (the thermostat), we started the car to check for leaks and it ran like utter garbage. I can hear a loud tapping sound coming from the engine, I have water coming out my tailpipes, and there is a nasty grinding sound. If I'm at low RPM and I give it WOT, it is somewhat spaced out but still loud. If I am at higher RPM (3500+) and I give it WOT, the grinding is insanely loud. It sounds like its coming from my transmission but it does it in neutral as well.

I don't want to have to save my cash for a rebuild... Anyone have any thoughts or ideas?

 

[jrichker]

And it's time to listen to your heart, Mr. Jones...

Remember the stethoscope? You own one but probably don't realize it: use a long screwdriver for one. If you don't have a long screwdriver, then a broom handle with a tin can screwed to one end is an excellent subistiute. Put it on the valve cover on the side of the engine where the noise is coming from, then put your ear on the handle (or open end of the tin can) and listen for the noise. A cylinder that is louder than the rest is the likely location of a hydraulic valve lifter with a leaky plunger or dirt in it. Move your stethoscope around to the various moving parts – alternator, water pump, smog pump etc., and try to localize the noise.

Pull the radiator cap, start the engine, fill the radiator to the top & look for a continous stream of bubbles. Lots of bubbles= blown head gasket. No bubbles, go to the next step.

Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. Since your car is an 88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 88's except possibly the Cali Mass Air cars.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

Fix the codes if any, and then if things aren't better, do the next step

Do a cylinder balance test to find clogged injectors or injectors that aren't firing. Warm the car's engine up to normal operating temperature. Use a jumper wire or paper clip to put the computer into test mode. Start the engine and let it go through the normal diagnostic tests, then quickly press the throttle to the floor. The engine RPM should exceed 2500 RPM's for a brief second. The engine will shut off power to each injector, one at a time. When it has sequenced through all 8 injectors, it will flash 99 or the number of the failing cylinder such as 22 for cylinder #2. Quickly pressing the throttle again up to 2500 RPM’s will cause the test to re-run with smaller qualifying figures. Do it a third time, and if the same cylinder shows up, the cylinder is weak and isn’t putting out power like it should. See the Chilton’s Shop manual for the complete test procedure.

 

[87'GTstang]

Very well-said Jrichker. The immediate thing I thought of when reading it was a blown head gasket. They cause poor power, loss of coolant (so check to see how much coolant you have), and a poor idle. My line of thinking is if it is going out the tailpipes, then the blown headgasket allows the water jackets to seep coolant into the cylinder and on the exhaust stroke, it pumps it out.

 

[ironheart1]

That's what I was thinking. At least head gaskets aren't expensive if one does the work themselves.

As far as that nasty grinding goes... I've failed to diagnose it at all. Could it be the flywheel? My clutch is really close to complete death.

 

[IndyBlk5.0]

Do a cylinder balance test to find clogged injectors or injectors that aren't firing. Warm the car's engine up to normal operating temperature. Use a jumper wire or paper clip to put the computer into test mode. Start the engine and let it go through the normal diagnostic tests, then quickly press the throttle to the floor. The engine RPM should exceed 2500 RPM's for a brief second. The engine will shut off power to each injector, one at a time. When it has sequenced through all 8 injectors, it will flash 99 or the number of the failing cylinder such as 22 for cylinder #2. Quickly pressing the throttle again up to 2500 RPM’s will cause the test to re-run with smaller qualifying figures. Do it a third time, and if the same cylinder shows up, the cylinder is weak and isn’t putting out power like it should. See the Chilton’s Shop manual for the complete test procedure.

Wow, I had no idea you could do that. Great info!