i bought a 93 camaro z28 8 cyl. it drives normally but shuts off and coasts while driving. had stopped in the middle of traffic a few times. i realized it had no maf sensor. i had one put in and thought that would solve the problem. it didn't. it started to drive like it was losing power and hesitate when i pressed the gas. recently i took off my radio face and noticed it didnt lose as much power as it had been. im wondering if this problem is the opti cable or the ignition coil, or something else. any help or similar experience is greatly appreciated, for this is my only car.
also, the previous owner was a "kid" who did stuff to make the car look cool and drive fast, if ya know what i mean.

 

Sure it's a stock '93 they did not have a MAS, so there should not be a pigtail to plug into the one you added ? You DTC 16 is missing opti low resolution pulses or extra opti high resolution pulses. The DTC will kill the injectors and stop the engine w/o lighting up the SES indicator. Usually caused by defective opti (could be oil or water contaminated), bad harness from opti to ECM or a voltage/ground supply problem. There are documented problems of aftermarket high power audio and speaker systems causing electrical interference with the low voltage opti signals. Are you sure disabling the radio actually effects the problem. Could be the previous owner wired the power source, grounds or speakers haphazardly. Try reseating the opti harness connections, make sure there is no oil or coolant leaking around the opti. Reset the ECM and see if the DTC 16 goes away w/o turning on the radio.

 

thanks bob. sorry for the late response. im still figuring out the site. lol! im gonna show this to my mechanic and see what happens.

 

ok so i took out the old opti and noticed some oil around and in the connection. i assumed it was from when my car was leaking and had to get the oil pressure part changed. i cleaned the connection inside and out and put in the new one. no problems for a few days. cleared the code. it worked til tonight, it shut down again. i scanned and got a code 16 still. also, i forgot to mention my air pump fuse blew i replaced both recently before i did the opti. sorry. could that mean my problem is the air pump? also, my mechanic is unsure now about the MAF sensor. are you sure it didn't come with one originally? im asking because in the haynes repair manual it shows the 8 cyl. camaro having an MAF sensor. is it because mine's a z28?

 

The AIR pump has nothing to do with the Opti or DTC 16, and does not prevent the engine from starting. If the fuse is bad it will set DTC 29, and the fans will run at startup. If the fuse continues to blow, pull the harness connector off the pump, and then put a new fuse in. Pump won't work, but it won't set a code either.

Not sure what "oil pressure part" there is to change on the front of the engine. There are several oil seals, including one for the Opti drive shaft, the water pump drive shaft and the crank seal on the timing cover. If those are leaking, its possible oil is still finding its way into the new Opti.

It's also possibly a harness problem. Check both ends of the short Opti harness for corrosion or damaged pins.

 

OP asked.. To the best on my understanding all '93 LT1's were Speed Density (SD) w/o a MAS. However I am not an expert or professional auto mechanic, nor do I have a '93 factory manual. I could be wrong and will stand corrected if someone with that knowledge else can respond to your question..... As you mechanic installed a MAS I would assume there was a harness connection he used, I really would like an answer on this myself.

 

You are correct there is no MAS on the 93 Z28"s

 

thank you all for your help. here's an update: i uninstalled the MAF my mechanic installed and rewired everything back to normal. my RPMs are working again and my car drives like it did before . im gonna clear the code tomorrow and see if it stops again. also, the wires were in a harness that i don't know the name of. i may replace that harness just to be safe. i was wondering if that also could read a code 16 on the reader?

 

it still shut off on me. im gonna replace my opti spark. i can get a non-vented one for cheap. does it have to be a vented one?

 

A 93 came with an unvented opti. That is the only one you can use. AC-Delco/Delphi is recommended.

I really don't understand how your mechanic could have installed a MAF. There would have been no wiring for it and the computer has no inputs for it and therefore could not read it (this is if it really is a stock 1993). I can't make any sense out of this scenario.

 

i got bad advice from someone who said they worked on camaros before. he said there was a part that shouldn't be there(a little black box). he said that was where the pigtail went. imy mechanic was also sure there was an maf sensor and used the wires from that box to hook it up.i undid it myself, put the box back on and my rpms worked again.

 

That "black box" would be the tach filter - another part that is unique to the 93. Your tach is driven off the coil, through the filter. 94-97 tach is driven from the PCM.

 

thanks injuneer. ill find a replacement soon i hope. do u know the name of the wiring harness its connected to?it may help me find it sooner.

 

ok so i got the new optispark in. am i supposed to reset the theft system? if so, how do i do that?

 

i just got off the phone with my mechanic and hes not sure if there's something special you have to do with the timing on the optispark.