Here we go again!

Started car this morning (72 degrees outside) and accelerates good. As the temp starts to climb(3-5 mins) the car starts to bog, pedal pressure seems tohave no affect until the car hits 3000 rpm and it takes off, or enough pedal and the car downshifts. IF i stop at a light, and pedal to floor , the car barely accelerates.

Noticed yesterday, turned car off for 5 mins and when trying to start, it did not want to start. Pedal to floor and started on 3 try. Motor just bogged until,slowly accelerated and when it hits 3000 rpm, takes off.

Cleaned the MAF sensor and throttlebody yesterday. not much help.

Was thinking of changing the coolant temp sensor, but when the car wouldn't start, now I'm thinking fuel pressure regulator or dirty TPS

IF i ONLY HAD A BRAIN,,,,,,,,,,

Joey

 

When it won't start, try spraying some starting fluid into the throttle body. If it then starts for a moment, then a problem with the fuel system.

Replace fuel filter if it has not been replaced for awhile. Air filter too if needed.

Then to test the fuel system, you need a fuel pressure gauge.

Complete instructions for testing the fuel system for your specific vehicle (the brain part ) would be in a factory service manual set (several books to complete set) which you can order from your dealer.

There are a LOT of different things to test and you need to know what pressures, what voltages or ohms when testing certain things with a voltmeter, etc. And these books will tell you what to test, what the test results should be for your vehicle, and what to test or do based on the results of the testing.

Here is an example of what all would need to be checked for a complete fuel system service...
Fuel Injection Service, Not Just Cleaning

And the problem might not be with the fuel system at all! Thus the reason for testing things. If everything tests ok, then check other things as directed by the books.

By using these books, you don't needlessly buy parts which are not needed. The factory service manual sets can cost around $150.00, but they quickly pay for themselves!


Additional checks for not starting...

Check the basics, Fuel, Spark, Air.

Fuel: While someone is turning the key to start, have someone else spray starting fluid into the throttle body. If you get a response, then this is a fuel problem.

Spark: Remove a spark plug and place the side screw portion against a piece of body metal or engine metal (grounded to battery negative/ground). Then watch as someone turns the key to start. See if there is spark. Advanced spark testing is to use a spark testing tool which would typically have a gap of .25 inch. You should see a crisp blue spark. This is a larger gap than a spark plug and tests that the coil is producing a high enough voltage. (Good spark as opposed to weak spark.)

Air: Slightly press on the accelerator while trying to start. Normally the throttle is completely closed and the IAC (Idle Air Control) valve adjusts to admit air into the engine. By pressing slightly on the accelerator, you are bypassing the IAC valve and allowing air to enter the engine.

Combination test: While someone slightly presses on the accelerator and turns the key to start, have someone else spray starting fluid into the throttle body.

 

In your last thread you said the pump was clogged with varnish... Did you check the fuel pressure yet?? Cleaning a pump isn't going to fix a worn pump & a weak fuel pump can cause strange things to happen.. I still think a fuel delivery issue, but you may have to tape a pressure gage to the windshield & record the pressures as problems are happening... Roger

 

What a mess!

After 3 days of T/Sing the car, I took it to a shop for diagnostics. They just called and said the machine can't communicate with computer which controls the engine. Is this under the dash? Ford wants $370 to rebuild it.

Should I look for anything before I take this route?


Joe in Miami

 

The computer makes the engine run. Sounds like it is toast.

Best to have a dealer replace something like that. There are all sorts of different "versions" of these, each slightly different from the next.

Also some newer vehicles have 24 different computers in the vehicle and 3 different computer local area networks. (I don't know exactly what your vehicle has). Anyway all these computers need to be able to talk to each other. Troubleshooting this can be complex to say the least!