pinging help

[HaulinTwinz]

Hey guys I'm stumped. I have a 94 5.0 stock motor. Only has cheap CAI. About 177k. I have run Seafoam, switched the air temp sensor, and just replaced the harmonic balancer new and stock. Above about 3000 rpm I get pinging. Have tried 87 to 91 octane with little help. I live in nor Cal. If and the stock h pipe has the cats gutted. Timing is at 10 and pings at 4500 rpm when down at 6°. I'm truly stumped any help would be greatly appreciated. thanks

[Trojan Horse]

Originally Posted by HaulinTwinz

Hey guys I'm stumped. I have a 94 5.0 stock motor. Only has cheap CAI. About 177k. I have run Seafoam, switched the air temp sensor, and just replaced the harmonic balancer new and stock. Above about 3000 rpm I get pinging. Have tried 87 to 91 octane with little help. I live in nor Cal. If and the stock h pipe has the cats gutted. Timing is at 10 and pings at 4500 rpm when down at 6°. I'm truly stumped any help would be greatly appreciated. thanks

1. Timing is not correct, maybe from to much slop in the timing chain/gears.
(You did remove the spout to set the timing and put it back in when finished correct?)

2. Possibly the ECU is malfunctioning and advancing the timing to much.

3. The pistons and or heads are carboned up really bad and the carbon is staying hot causing it to pre-ignite the A/F mixture.

4. Possible plug wire cross ignition. Wire as shown below.

[dreamstang]

also when timing was set was the spout connector removed?

[HaulinTwinz]

Spout connector was removed.

---------- Post added at 08:08 PM ---------- Previous post was at 08:01 PM ----------

Oh and btw plugs are stock motorcraft gapped at stock gap

[Trojan Horse]

Originally Posted by HaulinTwinz

Spout connector was removed.

---------- Post added at 08:08 PM ---------- Previous post was at 08:01 PM ----------

Oh and btw plugs are stock motorcraft gapped at stock gap

Try closing the plug gap up a bit and maybe modifying them as shown in the Useful Info sticky thread. That will expose the flame kernel to the A/F better and may help, or it may not. The choice is yours.

[HaulinTwinz]

Thanks for the idea trojan horse. I'm going to try and help my spark plugs out a bit when i get home tonight. I will keep you posted. Thanks again

[dreamstang]

Also check your fuel pressure.

[HaulinTwinz]

I was also wondering if fuel pressure does it. Does anyone know if you can rent the fuel pressure gauges from AutoZone

[dreamstang]

lack of fuel could definitly contribute to pinging. and yes you can rent a fuel pressure tester from autozone. also an aftermarket fuel pressure gauge to install permantly doesnt cost that much. that is if you want one.

[HaulinTwinz]

I think i finally got it, ran autolite 24s and gapped at .050. Pulled my EGR valve today to clean it and found out the previous owner took out the egr gasket. MORON. So cleaned it up set the timing back to 10 degrees and took a quick spin so far so good. Will update tomorrow when i have time to take it for a long drive.

[dreamstang]

Good news. Pay even closer attention whenever the weather gets warmer out.

[Dtibbz22]

People have told me using 91 or less octane gas won't cause pinging or knocking. One day I went
To a full serve gas station asked
For 93 and ended up getting low grade fuel I bought turbo 108 and within minutes the pinging stopped. Have not
Used less then 93 since. And no issues

[HaulinTwinz]

Tested the car today. Only drove 30 miles but hardly any pinging. I thought i heard some pinging but maybe not. Checking again tomorrow. Its got 87 octane in it now so i know with 91 it will be fine. And timing is at 10°. Crossing my fingers. And i wish i could get 93 octane instead of 91 with octane booster dumped in.