1991 L98 Pinging on Shell 93 Octane
09-23-2017, 01:42 AM
#61
Team Owner
You could easily be hearing LOTS of things. Your fuel injectors working could easily be confused with a pinging sound under acceleration with exhaust and wind noise.
I'd really be spending more time inspecting your under carriage. Your off roading adventure could have easily knocked a few things around, so I'd get it up on a lift. I think your pinging is now small potatoes.
I'd really be spending more time inspecting your under carriage. Your off roading adventure could have easily knocked a few things around, so I'd get it up on a lift. I think your pinging is now small potatoes.
The following users liked this post:
koritz123 (09-23-2017)
09-23-2017, 01:44 AM
#62
Team Owner
I have noisey fuel injectors and took a stethoscope to them to make sure the noise was coming from them so I'm pretty used to the kind of noise they make but maybe their sound changes on acceleration.
I think I have an exhaust leak now since the off roading last night. I have to get it up on a rack soon. Car drives straight and no leaks under the car.
I think I have an exhaust leak now since the off roading last night. I have to get it up on a rack soon. Car drives straight and no leaks under the car.
The following users liked this post:
koritz123 (09-23-2017)
09-23-2017, 01:45 AM
#63
Team Owner
From the seller:
Seals and gaskets through out the engine. Valve seals both heads. Checked for head warping. Heads straight as an arrow. Hash marks visible on cylinder walls and no sign of ridges. No wear on seats or springs. He removed the entire engine from the car and cleaned it up as well. I have the pictures.
I also have a long, long list of other parts electrical and otherwise replaced at the same time.
Seals and gaskets through out the engine. Valve seals both heads. Checked for head warping. Heads straight as an arrow. Hash marks visible on cylinder walls and no sign of ridges. No wear on seats or springs. He removed the entire engine from the car and cleaned it up as well. I have the pictures.
I also have a long, long list of other parts electrical and otherwise replaced at the same time.
The following users liked this post:
koritz123 (09-23-2017)
09-23-2017, 01:46 AM
#64
Team Owner
I can try and do a compression test.
Just took it out for lunch and I might be hearing things but it sounds like I can still hear an occasional ping in first gear .I turned on the air and I thought I heard it ping just a second or two and then also other times, although I can't replicate it every time.
Just took it out for lunch and I might be hearing things but it sounds like I can still hear an occasional ping in first gear .I turned on the air and I thought I heard it ping just a second or two and then also other times, although I can't replicate it every time.
09-23-2017, 02:43 PM
#65
Racer
Thread Starter
They are very noisy above the engine noise that's why I bought a stethoscope I wanted to ensure that the noise was coming directly from the injectors and you put the stethoscope on each injector and no question about it in my mind it's coming from the injectors plus the seller said they were oversized very noisy injectors.
09-23-2017, 02:45 PM
#66
Racer
Thread Starter
No he said everything is stock he said the previous owner which is two owners back put the oversized injectors in there but when he rebuilt the engine and any of the changes he made or basically just new parts he didn't add anything there's no headers there's no cam there's nothing like that.
09-23-2017, 02:47 PM
#67
Racer
Thread Starter
09-23-2017, 02:47 PM
#68
Racer
Thread Starter
I've been out driving today sometimes I hear nothing and sometimes I hear something I lugged it in 2nd and 5th a little today and I definitely heard pinging or knocking not sure what's going on it's here and then it's not here.
Last edited by koritz123; 09-23-2017 at 03:39 PM.
09-23-2017, 05:06 PM
#69
Racer
Thread Starter
I took the car into a shop and put it on the lift and had two guys look under it they said it's scratched up on the exhaust and underneath and the front part of the frame but they said other than scratched they didn't see anything dented in or any problems and they said that where the right passenger side MagnaFlow Muffler is it looks like the clamp has rotated and they said that could be the source of what I'm hearing as far as an extra exhaust leak now I'll have to take that in or somehow get under there and tighten it up.
Last edited by koritz123; 09-23-2017 at 05:07 PM.
09-23-2017, 06:41 PM
#70
Zen Vet Master Level VII
they said that where the right passenger side MagnaFlow Muffler is it looks like the clamp has rotated and they said that could be the source of what I'm hearing as far as an extra exhaust leak now I'll have to take that in or somehow get under there and tighten it up.
The following users liked this post:
koritz123 (09-23-2017)
09-23-2017, 07:35 PM
#71
Team Owner
They are very noisy above the engine noise that's why I bought a stethoscope I wanted to ensure that the noise was coming directly from the injectors and you put the stethoscope on each injector and no question about it in my mind it's coming from the injectors plus the seller said they were oversized very noisy injectors.
Still, the size bothers me since we have no clue. I suggest you dump it for a set of reman ones from FIC. You cannot simply toss a set in there that is different sized and expect it to work. 22 to 24, sure. much more or less, well....
09-23-2017, 07:35 PM
#72
Team Owner
No he said everything is stock he said the previous owner which is two owners back put the oversized injectors in there but when he rebuilt the engine and any of the changes he made or basically just new parts he didn't add anything there's no headers there's no cam there's nothing like that.
09-23-2017, 07:37 PM
#73
Team Owner
The following users liked this post:
koritz123 (09-23-2017)
09-23-2017, 07:38 PM
#74
Team Owner
I took the car into a shop and put it on the lift and had two guys look under it they said it's scratched up on the exhaust and underneath and the front part of the frame but they said other than scratched they didn't see anything dented in or any problems and they said that where the right passenger side MagnaFlow Muffler is it looks like the clamp has rotated and they said that could be the source of what I'm hearing as far as an extra exhaust leak now I'll have to take that in or somehow get under there and tighten it up.
09-23-2017, 11:08 PM
#75
Racer
Thread Starter
09-23-2017, 11:14 PM
#76
Racer
Thread Starter
09-23-2017, 11:23 PM
#77
Racer
Thread Starter
I think your PO is full of it. I have yet to see a set of injectors that make noise over the engine. IOW, you can hear them with a stethoscope but I have yet to be able to stand around the car and hear it.
Still, the size bothers me since we have no clue. I suggest you dump it for a set of reman ones from FIC. You cannot simply toss a set in there that is different sized and expect it to work. 22 to 24, sure. much more or less, well....
Still, the size bothers me since we have no clue. I suggest you dump it for a set of reman ones from FIC. You cannot simply toss a set in there that is different sized and expect it to work. 22 to 24, sure. much more or less, well....
09-23-2017, 11:29 PM
#78
Racer
Thread Starter
With the hood up my neighbor my mechanic friend and myself heard some kind of tapping I recorded it if there's any way I can put it out on this thread let me know. The tapping was noisy enough to Warrant getting a stethoscope so I can eliminate lifters or tappets or whatever which wouldn't make any sense anyway if the upper part of the engine has just been rebuilt if the guy knew what he was doing. So when I put the stethoscope on each injector I could tell immediately the noise I was hearing with a hood up was that coming from the injector some injectors seemed a little more noisy than others. Again I recorded this if there's any way I can get this recording to you I'd be glad to send it to you.
09-24-2017, 08:50 AM
#79
Team Owner
Search on eBay. http://www.ebay.com/itm/SNAP-ON-TOOL...4AAOSw4QVZv7mb
Now get the cartridge for this and you are in business.
Maybe http://www.ebay.com/itm/SNAP-ON-TOOL...cAAOSwLdNZv75-
Now get the cartridge for this and you are in business.
Maybe http://www.ebay.com/itm/SNAP-ON-TOOL...cAAOSwLdNZv75-
Last edited by aklim; 09-24-2017 at 08:55 AM.
09-24-2017, 08:57 AM
#80
Team Owner
If I got the remanufactured set from fic is there any way for me to know that the person who put the oversized injectors in didn't have the ECM programmed for those injectors. Right now everybody I've talked to said the software to reprogram the ECM is gone for a 91 nobody has it anymore that's why the car can't be Performance Tuned or Dyno Tuned. I followed through on your suggestions and other people's as far as contacting people who supposedly could Dyno tune the engine and when I got to the person who knew what they were talking about all the software is gone nobody carries it anymore they threw it out all they carry is newer software. I'd like to know if the ECM programming is stock before I go putting another set of injectors in there at $400 or 500 a pop. But your suggestion makes sense I just like to verify the ECM to see if its stock.