knocking (95 se-r) and power loss

jon_Gee · Aug 5th, 2003, 09:58 AM

I've been experiencing some knocking at times when i first start my 95 se-r, and can't fiugre this out. I've seen some discussions on fuels, but can't remember if anyone was able to conclude anything.

It's a sporadic problem, and the only consistent factor seems to be that i was using 89 octane with 10% enthanol (which the great state of iowa says is fine for your car

). It would happen just when I started, then, naturally, the knock sensor would pick it up and lean the mixture. After this, I would in turn experience less power. I don't mind paying for the 91-92 oct gas, but I still find it odd that it would happen with 89 oct, unless I had some internal problems.

I had my timing advanced slightly, and it would be a less consistent problem when I decreased the timing, which makes sense.

It's kinda hard to judge overall w/o a track nearby, but I feel as though my car has lost some serious power over the last 2 years i've owned it. I've driven it from 84k miles up to 116k in that time.

When I was young and foolish, I can remeber an incident where I put some leaded 108 (+/-) oct fuel in there, maybe 1/3 of a tank, which may have done something.

What I would like to find out is 1. Has anyone had problems with ethanol fuels; 2. What damage might I have caused by allowing the 'starting knocking' problem to go on for a while; 3. What could I have ruined with that leaded fuel experiment back in the day; 4. What maintenance schedule items might be affecting me?

Any thoughts are great, and thanks for reading.

Token Moron · Aug 5th, 2003, 01:57 PM

Quote:

. I don't mind paying for the 91-92 oct gas, but I still find it odd that it would happen with 89 oct, unless I had some internal problems.

the lower octane u go, the more problems with pinging/knocking u will have.........if u advanced your timing, u MUST run 91 or higher octane fuel....u just have to.

Quote:

What I would like to find out is 1. Has anyone had problems with ethanol fuels; 2. What damage might I have caused by allowing the 'starting knocking' problem to go on for a while; 3. What could I have ruined with that leaded fuel experiment back in the day; 4. What maintenance schedule items might be affecting me?

1.we dont have that in CA
2.no damage really, but if let it go without fixing it.....look for a new engine
3.u coulda ruined your whole fuel system(injectors in particular...some seals)
4.hard to say, if u advanced your timing TOO much, youre not gaining anything just asking for trouble, and if its deadvanced too much youre loosing power, if u want to have advanced timing, the most u can do is 20* on your sr20, but u must run high octane, and since u probably have low octane right now, deadvance your timing and run 2+ tanks of high octane before u advance your timing again, problems should be solved

Irons · Aug 5th, 2003, 02:31 PM

1) In Buffalo, our gas has ethanol. No problem, but timing isn't advanced.
2) No idea.
3) What AJ said
4) Maintance maybe your power loss.

Personally I would do this.
1) Oil Change. (esp, if you don't do this regularly).
2) Change plug, wires, cap, rotor. Big loss here if you don't do this regualarly, ie 2yr's or so).
3) Put timing back to stock and see if problem persists.
4) If it does try Octane boost when timing is advanced and see if problem goes away. If it does not get the car looked at, but don't mention prior indescretions.

jon_Gee · Aug 5th, 2003, 03:03 PM

Thanks so far guys.

I do regular oil changes 3K miles with only moble one.

Should I try to find a place to have my injectors flowed, to see if they performing baddly? I replaced the o rings back in June and the fuel filter as well. I'm wondering what specific areas of the fuel system could then be in question from the leaded gasoline. I'd think that would limit it to being the injectors themselves.

I also wonder what effects the would leaded gas have had on my cat. Would it mearly reduce its ability to attack smog, or would it actually restrict flow in some way?

Token Moron · Aug 5th, 2003, 07:35 PM

Quote:

Originally posted by jon_Gee
Thanks so far guys.

I do regular oil changes 3K miles with only moble one.

Should I try to find a place to have my injectors flowed, to see if they performing baddly? I replaced the o rings back in June and the fuel filter as well. I'm wondering what specific areas of the fuel system could then be in question from the leaded gasoline. I'd think that would limit it to being the injectors themselves.

I also wonder what effects the would leaded gas have had on my cat. Would it mearly reduce its ability to attack smog, or would it actually restrict flow in some way?

ya, get your injectors clean with ultrawave sound at a shop(trust me on this)

the specific areas would be the injectors, filter, fuel pump

lead can and will damage the pump and would eat away at rubber

the effects your cat would be build up of excess carbons that in time will burn up your cat.....and thus not doing its job with smog

Mr.Barrie · Aug 5th, 2003, 09:53 PM

You can try a can of BG44K Quick Clean. It is a damn good product and will clean your entire fuel system. You have to put it with a full tank. I usually run my tank down half way and then fill it up again to get the most out of one can. It's around 24 bucks a can.

jon_Gee · Aug 6th, 2003, 12:59 AM

i've been using seafoam, which is considered to pretty damn good stuff. I put some through the vacumn line from the pcv valve, so that it should be doing something for the injectors. I will look into the ultrasonic (see if it's available nearby..des moines maybe), and look up some stuff on that bottled product as well.

I should prolly take it upon myself to have a peek at my valves, see what condition they are in. It may also be time for a new timing chain. Rebuild, anyone?

I think iminently, i'm going to replace the clutch, which the used car dealer i bought it from put in (2 years, 32k miles ago). I had the car for 3 days before the clutch that was in it went out. That sucked, but I don't doubt that they used a less than optimal clutch.

Also, my i had to put on temp CV boots (the split kind) this past week. The metal noise in turns is still present, so i'll get half-shafts at the same time.

I need a new credit card.

himilefrontier · Aug 6th, 2003, 12:35 PM

Here are some alternate things that can cause knocking nad pinging:low coolant level that allows the head to get too hot, bad thermostat and also excessive combustion chamber deposits that become pre ignition hot spots.