Caught it pining for a second (till I lifted off) around 5-6 rpm under 80% throttle. It used to do this before I replaced plugs and turbo inlet duct 6 months ago, hasn't happend since then, now again wtf! 88 TII 40K on motor NO MODS exept replacement factory type K&N.

I plan on replacing plugs and running injector cleaner. Don't know what else to do. Could use some advice.

 

you may want to check your timing, and maybe retard it a couple degrees. also you may want to look at the fuel filter, fuel pump voltage.
i am assuming you're using 91+ octane gas too

mike

 

I always heard that we should use LOW octane gas in our cars. I had a similar problem, and had to retard the timing........

 

If you are pinging try running 91+ gas, some say it solves that problem..I for one use it but only due to mods and reasurance and because I like to spend a lot of money on gas.

 

thanks, but would retarding the timing on a stock setup be a patch job, covering up for the real cause of the detonation?

 

sorry i use only 92 octane

 

Well i run 93 Octane thats the highest we can get here at the pump unless, you go to the track or go north about 25 miles or so to get Sunoco high octane. I dont know if you can actually use 91 octane on a T-II ?
But i recomend you change your fuel filter, and also plugs. Also how many pounds of boost are you runnin ?
I have a EGT in my T-II, and i use it as a reference as well as my boost gauge. Good Luck

 

So it could be restricted fuel flow. Is it a big job to replace fuel filter?

 

I'm running stock boost, can't say exactly how much, the needle on my gauge goes about 85% to max, if it's accurate. I have one bad muffler too which might be fooling with back pressure.

 

well, if its stock it shouldnt detonate, but you dont want to blow the motor while you look for other problems

mike

 

Non turbo cars, low octane

Turbo cars, high octane.

 

really, dang I been usin high octane cuz I thought we shold....

- James
88 SE

 

hehe...high octane gas on a stock n/a will decrease performance.

 

The owners manual calls for a minimu of 87 octane for an '89 TII. The car should run fine on it if it is 100% stock. However, I use 93 (premium) just for the extra safety factor. I have the same problem. My car is an '89 with 48,000 miles on the ORIGINAL engine. Car was cared for immaculately. Now, I'm getting detonation when I open her up. I've tried...timing, plugs, fuel filter, injector cleaner, and checked fuel pump pressure...nothing has helped. I'm starting to think I might have a bad injector. I hear a "sucking" sound around the BAC area but I have not been able to find a leak. The car idles perfectly and starts right up....I doubt it's a vac. leak. So...if you figure it out, please let me know before I blow up a nice, all original TII !

 

is it possible, that redlining it at 85% throttle - in other words spooling up the turbo and getting boost without flooring the gas - causes it to run lean? Cause that's a habbit I have I never really floor it, just give it enough gas to get a good rush....then ping! Or letting off just a little under full boost, decreasing fuel flow - i might do that too. Cause mine doesn't ping all the time.

It's almost like I can tell by the feel of the power band when it's going to ping. I revs up perfect and pings at 5500, when it doesn't rev up perfect (you can feel the timing is different) is doesn't ping at all. Could be me.

I'm picking up plugs and fuel filter after work today.

 

My integra's engine had a mild but persistent pinging problem until I rebuilt it. There was a lot of carbon built up inside it which may have been the cause of the pings. Every 13b engine I have seen pics of when freshly taken apart has carbon on the rotors, some times lots of it (like with my S4 NA engine that I am rebuilding now). Maybe carbon build-up is the cause of your pings?

 

Low compression helps cause pinging I think.