joed

I hahe a 94 T/A with the 5.7lt1 and cannot pull any codes using a jumper conected to a/b. The SES light lights up without the jumper, but if i install the jumper and turn the ignition on I don't get a code 12 and the rad fans come on instead. I'm having trouble with the engine pinging when you step on the gas with the car in park. It was worse before i changed out the dist, coil and ign module. If the car wasn't so fun to drive I probably would have junked it by now.

Thanks in advance
joe

shoebox

You cannot pull codes with the "paper clip" method. You need a real scanner to do it.

slopokrodrigez

How many miles on it? How long have you owned it? What type of "internal" cleaning have you done like BG or Seafoam? Does it still have cats? If so have you checked for backpressure? Could it be you're hearing something tapping and confusing it with "knock" or "ping"??????? Heard broken flexplates before sound strangly formiliar but you didn't mention the tranny either.

We need more info than you are giving up so far.

joed

The car has 150,000 miles, auto trans, have not run engine cleaner in itand i've owned it for 3 years. The car is acting the same as it did last year before I replaced the opticrap. The new dist was complete oem unit from Jason. I've replaced the opti again using the old cap and rotor from the dist I bought last year, I changed the ign coil and module. I'm running 93 octane fuel. The engine pings when it's cold only if you step on the gas pedal fast regardless if it's park or in gear. as the engine gets hoter the pinging is real bad and barely makes it home and the engine starts to break down at around 4500 rpm. The car was running fine without any hint of a problem until one day it **** the bed. I only drive the car less than 10K miles a year. I tried to pull the pcm codes following the instructions in the Chilton manual.

Help
joe

slopokrodrigez

Well not sure what the chilton manual says but it should say only 93 codes can be gotten with a wire jumper. See what year it's for. Like Rob said, you have to scan 94 and up to get those codes and Autozone can't do those before 96(pre OBDII).

You also didn't mention if you still have a cat. You could try to disconnect it and see what the car does BUT I doubt you could hear anything, much less ticking once you did.
Incorrect spark timing can contribute to preignition. Have you ever checked to see where the rotor is pointing when referenced to a cylinder?

Perhaps it's time to move on to the fuel system. Could be you are running lean which can contribute to preigniton. Unfortunately, even if you check fuel pump pressure and injector pulses, you may still not find the lean problem. But both should be checked. You can see if the plugs look like they have been burning lean.

Carbon deposits in the cylinder can make local hot spots that can also contribute to preignition.

moparman

Yes, you need a real scan tool. Look here for some refurbs: www.autocheckup.net/

joed

I ordered the Autoxray XP240 Scanner last night and hopping it'll help.

MyShibbyZ28

Or just take it to a dealer and have them check. But who wants to give them more money anyways...

joed

I'd would take to the dealer but I'm scared they would stick it to me without even lubing me up first !

moparman

They would charge you as much or more than you paid for the scan tool.

joed

Finally was able to scan and after clearing all faults started from scratch. Noticed pcm is staying in open loop, right side 02 staying at 444 mvolts and left side bouncing up and down. Engine still runs like crap once it's warmed up and no new codes loged. Anything other than the right bank 02 sensor staying at 444 mvolts could cause pcm to stay in open loop once engine is warmed up?

the wife says it's either the car or me going to the junk yard if the car isn't running soon, I think she would prefer me going but I won't give her the satisfaction.

moparman

The steady reading O2 needs changing. Change that and see if that cures the problem. Or, you can swap the sensors and see if the problem moves with the sensors.

joed

What tool does it take to pull right side 02 sensor out ? The exhaust flange is to close to use either a sensor socket or a deep socket. Not enough room for open end wrench either.

calaban

Advance carries an Actron code scanner that will scan 94 models for around 30 bucks. I was looking for myself this weekend. But I have a 95 with the OBDII connector and OBDI computer. Had to let my father in laws mechanic scan it with his high dollar Snap-on deal.

Slayer63b

I have a 93 z28. How can i pull codes with a paper clip. Just stick it in a/b. And how do I tell what the code is. I don't see it in my chilton manual. A link would be great.