QuestionMy 1987 Chrysler New Yorker Multi Port Fuel injection when driving on level ground runs fine. When I punch the gas is shifts down as is should, but it seems to flood out like the old carberator cars will when you pull the choke out. My car wil bog down until you let up on the gas. Black smoke pours out the exhaust pipe until I let up on the gas and the trany goes into high gear and we are running level and smooth again. I know when it acts like this we have a real rich mix.
I have changed the OXY sensor and it had a lot of soot on it. I pulled out the new oxy sensor and it had a lot of soot on it after only 2 or 3 steep hills when I had to give it a lot of gas. I am sure the catalytic converter is fine.
So far I've changed the Oxy Sensor, Knock Sensor, Coil Pickup module, engine control computer also known as ECU and the fuel filer. I'm checking the fuel pressure regulator next. I own 3 of these cars so parts are not problem,
I don't know what else to do, hope you can help.
AnswerHi Tony,
Checking the fuel pressure is reasonable. The other part that might be causing the problem is the throttle position sensor which might have a discontinuity in its resistance coil. But don't overlook the possibility that the engine controller has already noted a problem with a component that it oversees and put a coded fault entry in its memory. The most useful thing to do would be to try to get the fault codes that may stored in the engine controller memory to readout. Try using the ignition key: turn it "on-off-on-off-on" and leave it "on" (doing this quickly, no longer than 5 seconds). By "on" I mean just the normal position when the engine is running, not the cranking position. The 'check engine'light will remain on when you leave the key in the "on" position with the engine still not running. But then watch the 'power loss' light to begin flashing, then pause, flashing, pause, etc. Count the number of flashes before each pause and keep track of the numbers. Repeat the readout and verify the counts are correct. Then group them in pairs in the order that they came out, thus forming two digit numbers. You may notice that the pause is shorter between the digits of a given number, and longer between the numbers themselves. Then send me a 'follow-up' question telling me the results of your readout. By the way, 55 will be the last number (two groups of 5 flashes each) and that is the code for "end of readout".
I have the troubleshooting manual for the turbo engines and we can look up the possibilities of what is wrong based upon what fault codes you show. I also have the shop manuals for the '87 model year, it we need them.
There is also an essay on fault codes at the site:
http://www.allpar.com/fix/codes.html
which gives the meaning of the code numbers. But then you need to get specific info for what exactly might be the diagnostic tests or parts to replace to complete the repair.
So give that a try and let me know what you learn.
Roland
