Spark knocking galore...

Stangswagalicious · Jun 9, 2022

Friends, im back at it again with some more bull ish to throw at you.

So, my car is spark knocking and its pretty hard to avoid. Knocks mildly with mild throttle starting around 2k rpm and gets pretty aggressive above 3500k WOT. Its not nearly as bad when i run 93 octane but i really dont want to because gas is expensive as balls right now.

I have many new parts installed. Some a relavent some are not but im just going to throw it all out there. Again, all of these listed parts are brand new

Parts: 3 core radiator, water pump, timing cover, timing chain and sprockets, new 24lb injectors, new MAF/CAI (calibrated for the 24lb injectors) new 70mm throttle body (injectors, maf and tb were all american muscle power adder kit thing) new iac valve, egr valve and position sensor, alternator, distributor/cap/rotor, tfi module, ignition coil, plugs/wires.

I have looked around a bunch on the interwebs. I have ran through the surging idle checklist, and as far as i can tell, the o2 sensors and the tps are the only thing left. Cars 26 years old. I may just replace em to keep it dependable. I have checked the voltage of the tps rece tly and it seemed to check out just fine. Even tho (from what iv read in the haynes manual) the tps is non adjustable on the 94-95, i still got it to sit right around .91 volts at closed throttle. However in Theory, it shouldnt matter where its baseline is set since the computer re learns its idle position every time its started. I have PROPERLY set the idle, (unplugged iac, adjusted stop screw, unplugged battery for 15 min ect) idles right at about 650-700

Some other information i have is that i just changed plugs again (less than 10k miles on them) just for a health check and they all 8 looked like shes runnin pretty lean. I have a feeling that has a lot to do with the spark knock right there. I pulled engine codes doing all the self test. Koeo:111 koer:111 (both mean no codes present) and when i did the cyli der ballancer test i got 9 flashes. (Not sure what that meant) also, i brought the timing from 14 back to 10 in hopes that would help be able to run 87. Lastly, i read somewhere that the engine not running warm enough can cause some weird thi gs to happen. I posted pics of the spark plugs, and the operati g temp after iv driven around a while. The thermostat is new also, but i can never seem to get the car to run warm how it should be. The spark plugs are 1-4 on the first set of pics and 5-8 on the second. Cyl #3 is only darker because i touched the tip (giggity) with my greasy hands

Im sure im forgetting other info that could help. But thats most of it. Any questions please be ask away. This car has been a real pain in the ass

Im sure theres in

lwarrior1016 · Jun 9, 2022

Have you checked fuel pressure or replaced the fuel filter? Also, has this can been tuned? Does it have the stock cam in it?

Wmac · Jun 9, 2022

Ping start after installing the maf & injectors?

You could try autolite 24's and dial back the timing to 8*.

Agree to check fuel pressure and install new fuel filter if not recently changed.

joemomma · Jun 10, 2022

Agree with a fueling issue - fuel filter replacement and pressure check. Definitely looks to be running lean based on those plugs.

You say the car isn't getting up to temp - did you install the thermostat wrong?

Stangswagalicious · Jun 10, 2022

Friends, as expected, i did forget to mention i put a new fuel filter in as well. I have checked fuel pressure but it wasnt recently. 30ish with vacuum plugged up and a little over 40 with it off. Also, my dear friend who i bought the car from said he had this same issue with the car the whole time he owned it. Roughly 5 ish years. He just opted to put 93 in it and dealt with it. So, apparently, this isnt a new issue. And lastly, i put the spring of the thermostat inside of the motor. So unless it got stuck, i have no clue whats up. The thermostat should regulate the temp of the matter no matter how big the rad is so idk whats up with that. But could it running cooler honestly have anything to do with it?

Stangswagalicious · Jun 10, 2022

No the car has not been tuned and i believe the car does in fact have the stock cam in it

95opal · Jun 10, 2022

Stangswagalicious said:
Friends, im back at it again with some more bull ish to throw at you.

So, my car is spark knocking and its pretty hard to avoid. Knocks mildly with mild throttle starting around 2k rpm and gets pretty aggressive above 3500k WOT. Its not nearly as bad when i run 93 octane but i really dont want to because gas is expensive as balls right now.

I have many new parts installed. Some a relavent some are not but im just going to throw it all out there. Again, all of these listed parts are brand new

Parts: 3 core radiator, water pump, timing cover, timing chain and sprockets, new 24lb injectors, new MAF/CAI (calibrated for the 24lb injectors) new 70mm throttle body (injectors, maf and tb were all american muscle power adder kit thing) new iac valve, egr valve and position sensor, alternator, distributor/cap/rotor, tfi module, ignition coil, plugs/wires.

I have looked around a bunch on the interwebs. I have ran through the surging idle checklist, and as far as i can tell, the o2 sensors and the tps are the only thing left. Cars 26 years old. I may just replace em to keep it dependable. I have checked the voltage of the tps rece tly and it seemed to check out just fine. Even tho (from what iv read in the haynes manual) the tps is non adjustable on the 94-95, i still got it to sit right around .91 volts at closed throttle. However in Theory, it shouldnt matter where its baseline is set since the computer re learns its idle position every time its started. I have PROPERLY set the idle, (unplugged iac, adjusted stop screw, unplugged battery for 15 min ect) idles right at about 650-700

Some other information i have is that i just changed plugs again (less than 10k miles on them) just for a health check and they all 8 looked like shes runnin pretty lean. I have a feeling that has a lot to do with the spark knock right there. I pulled engine codes doing all the self test. Koeo:111 koer:111 (both mean no codes present) and when i did the cyli der ballancer test i got 9 flashes. (Not sure what that meant) also, i brought the timing from 14 back to 10 in hopes that would help be able to run 87. Lastly, i read somewhere that the engine not running warm enough can cause some weird thi gs to happen. I posted pics of the spark plugs, and the operati g temp after iv driven around a while. The thermostat is new also, but i can never seem to get the car to run warm how it should be. The spark plugs are 1-4 on the first set of pics and 5-8 on the second. Cyl #3 is only darker because i touched the tip (giggity) with my greasy hands

Im sure im forgetting other info that could help. But thats most of it. Any questions please be ask away. This car has been a real pain in the assView attachment 18128 View attachment 18130 View attachment 18131 View attachment 18132 View attachment 18133

Im sure theres in

You say you went through the surging idle check list. Are you experiencing surging idle along with the lean condition? If so id suspect vac leak. Carbon build-up on the piston will also lead to spar knock. A can of seafoam will clean them up a bit.

Stangswagalicious · Jun 11, 2022

So, i did go through the surging idle check list. It actually idles really good now. Very little sway in rpms. Next paycheck im going to just put a new tps on it to be sure and i may go ahead and replace the o2 sensors. They could be as old as the car. Otherwise, honestly... what cpuld cause the whole motor to run so lean?? Im pretty comfident theres no vacuum leaks but hell. Theres a lot of vacuum on this car. It still has all the smog shit and egr but one day when i put long tubes on im deleting them both. That will clean up the engine bay, eliminate a lot of useless vacuum shit and sound spectacular.

ttocs · Jun 11, 2022

I would guess the maf/injectors myself. The best way to upgrade these would include a tune but then unless you are into the heads/cam/boost area you have no need for 24 lb injectors.

95opal · Jun 12, 2022

You really need to see FP under load. When experiencing a lean condition.

Stangswagalicious · Jun 12, 2022

So under a load, would that mean i cant do it sitting still? I can rev the motor in the garage in all but then in my head its not under an actual load. The MAF and injectors are 6 months old. And are supposedly calibrated for each other.

What should i expect when testing fuel pressure under load? How would you do it? Are we tadgetting the fuel pump here??

Food for thought. (At least for my self) just because you have the pressure, doesnt alway mean you have the flow.

You guys have been really awesome so far and i thank you all for the time

Stangswagalicious · Jun 14, 2022

Can a brothuh get a bump...

Stangswagalicious · Jun 14, 2022

So, i have an update. I had an epiphany today. When i replaced the timing components, i installed the stationary timing indicator a little crooked and it was rubbing on the balancer. Incredibly annoying noise. So i bent it up to fix it and apparently i bent it the wrong way. I re timed it today to what looked like 6 degree btdc, and now im having a hard time getting it to spark knock at all. Im confident i bent the tab the wrong way. So when i thought i was at 14 i was probably closer to 20) However, i ordered a tdc finder tool that goes in #1 spark plug hole. Im going to find tru tdc and see if the balancer is aligned and hopefully with that i can bend the tab back into place and time properly. Il update you all with the timing issue when i get the tool. (Hopefully this weekend) and when i do that, il check fuel pressure under load and get back to you. Its not spark knocking now but this still doesnt solve the lean condition... i should get back with you all by monday!!!

Thank again everyone for taking the time to help. I really like it here!

lwarrior1016 · Jun 14, 2022

Well, I’m glad you finally got something going in the right direction.

And, we are happy to have you here.

Stangswagalicious · Jun 15, 2022

So... although it did help, it did start pinging again but not as bad. I had yet another epiphany as well tho. The day i got the car i noticed a certain uh.. hissing noise that comes from the glove box area during certain throttle positions. Never paid it anymind. I figured it was some sort of vacuum canister or something. But now that i think about it, i believe it is actually a massive vacuum leak. Anyone know what lies behind the glove box to look for?!

lwarrior1016 · Jun 15, 2022

All of your a/c controls are back there. Sadly, you have to pull the dash to access them. You could follow the one small black line that goes through the firewall by the heater hoses. You can disconnect and cap that to see if it changes what you hear inside. That’ll just remove all vacuum from the dash.

Stangswagalicious · Jun 15, 2022

Yikes. I couldnt live without the ac now... i wish i could describe the noise it makes. But its definitely comming from behind the glove box there and its definitely air moving. Is there any egr or smog controls back there? If mh memory servrs correct, it seems like some of the smog lines run in that area as well.

The problem i face with this, is when i bought the car, shortly after i found that the ac control vacuum line was broken in several places behing the intake plenum. I feel like it was making that hissing noise before i ever fixed that line...

The car is old. Maybe that noise is normal? Anyone ever noticed a similar sound?