car runs terrible :(

F

frankjc

Registered
Hi. For the last couple days my 95 Mark VIII has been running bad. It idles very rough, and kinda shudders when taking off. Once in a while when I punch the gas, I hear what almost sounds like a backfire. It does it in park, neutral, and in drive, and at low speeds. It seems better at around 50 mph (I think). Thinking back a week or so ago there were a few days when it idled higher than normal. There was also a couple days when when it was very cold and it idled very low. Now it idles a little under 1k, but very rough. Check engine light is on, and i have a list of codes (I think I got them right) 32,73,27,11,72,32,75. Not sure what to do next. Any suggestions would be appreciated.
 
The codes should have more to them. Like Po21 etc. What you describe sounds like a misfire condition. Could be other things though. Start by decoding the codes. Did you have a code reader? Google the full codes and you will find some decoding lists.
 
32 egr positioner sensor below closed limit
73 insufficient throttle positioner (TPS) change during dynamic response test
72 insufficient manifold absolute pressure (MAP) change during dynamic response test
75 brake on/off (BOO) circuit closed
 
ok. what i did so far, as someone advised me to do, is get a spary bottle of water and spray the plug wires. they are arcing everywhere. i hope this is the cause. these wire sets are expensive. what plugs are recomended for this car?
 
I recently got a set of plug wires from summit racing. they are just a stock replacement but only cost about $60 after tax. So far, so good for me. May save you a bit of cash over a parts store.
 
I got a set for around $60 from NAPA. The car runs a LITTLE better, but still has problems. I haven't had much time to work on it, too many other things going on. I am starting to suspect a vacuum problem. I recall having a DPFE code at one point, which I never addressed. It seemed at one point a while back that turning the heater on sometimes shut the check enging light off. Last summer I replaced that T fitting that rotted. Some of the other rubber connectors, like the one on the PCV look pretty bad.
 
frankjc said:
32 egr positioner sensor below closed limit
73 insufficient throttle positioner (TPS) change during dynamic response test
72 insufficient manifold absolute pressure (MAP) change during dynamic response test
75 brake on/off (BOO) circuit closed
Click to expand...

You need to redo the code check. 72, 73, 75 were because you did not complete the throttle snap test or press the brake pedel (and probably cycle overdrive switch).
 
I did the KOEO test. Should I have done the things you mentioned with the engine off? If so, are there instructions I should read before pulling codes again?
 
I drove the car about 12 miles, half hour or so, when I got to my destination, I put a jumper wire between the self test input and sig return, turned the key and counted the flashes.
 
Opps, sorry....I'm just going to type it out, lol. Those codes were set because the key on engine running (KOER) steps were not taken. When diagnosing, you need to address all KOEO (off) codes first, but because you had the KOER codes present, you should clear them and start over.

Clear the codes by pulling the negative battery cable for 30 minutes. Drive the car for a while and cycle the key on/off a few times (i.e. go to the store, get gas, etc) and then recheck. Write down all KOEO codes and then perform the KOER test and write down those codes.
 
I believe the C is for Copper. I just use Autolite 764's, copper and 99 cents or less.
 
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