Bucking, kicking, and screaming... Well sputtering...

jerd_hambone · 08-27-2009, 11:49 AM

So my car has a really odd problem. At completely random points in time, you will be driving and all of a sudden it starts bucking and kicking like you are tapping the gas really fast. It does it in every gear. If you try to floor it, it just falls on it's face and it is pretty much like you let off the gas completely.

I don't know what to do about this, and I can't figure it out.

Oh, in case you were wondering it's a 89 GTU.

Phoenix7 · 08-27-2009, 02:02 PM

and you've checked the TPS? All within specs?

dudemaaan · 08-27-2009, 10:44 PM

how modified is the car? My car does it sometimes too, i have minimized it by tuning, but it still exists. I read an article explaining that the design of the rotary allows exhaust gases to mix with the fresh mixture in certain situations and it causes a misfire and results in the bucking. The technical name is 3:3 ignition mis-fire. here's a link to the pdf.
http://foxed.ca/rx7manual/manuals/RE...amoto-1981.pdf

jerd_hambone · 08-28-2009, 10:37 AM

I forgot to add that the only way to stop it is to let the car set for 24+ hours and when you restart the car the next day to rev the holy mother out of it and it clears up.

I've not checked the TPS, I may have to do that.

JL1RX7 · 08-28-2009, 10:53 AM

Check all of your grounds. I know if they are bad or corroded that can lead the car to do some weird stuff.

nvno1 · 08-28-2009, 12:03 PM

Quote:

Originally Posted by jerd_hambone

I forgot to add that the only way to stop it is to let the car set for 24+ hours and when you restart the car the next day to rev the holy mother out of it and it clears up.

I've not checked the TPS, I may have to do that.

Yeh the TPS will trip like that. Also have to changed the brand of gas you normally use.? I used some cheap gas one time and that was the last time that motor ran. not trying to scare you.

jerd_hambone · 08-28-2009, 01:42 PM

I always use good gas, premium.

I've been thinking that it's the TPS, but figured I'd try to see what everyone else thought.

And it's not the typical bad ground bucking.

JL1RX7 · 08-28-2009, 02:32 PM

With NA you can use cheap stuff. 87 octane works just fine. Also did you check you battery cables and spark plug wires?

jerd_hambone · 08-28-2009, 07:45 PM

Battery is getting juice, volts don't drop when it does it. The spark plug wires are about to get changed.

I used higher octane and the felt more peppy a tad and got better mileage. So I dunno.

NoDOHC · 08-28-2009, 10:33 PM

My '91 likes premium more than regular.
My old '86 never cared at all, with the 8.2:1 rotors it really doesn't car now.

On the original topic: I had my '86 buck and shake once, but it was because I had the leading and trailing plugs connected backwards. Obviously, that doesn't come and go.

I am guessing that you have a bad connection or a fueling issue (loose sock or something).

This is an interresting problem, keep us posted.

jerd_hambone · 08-29-2009, 11:29 PM

I will definitely keep it updated.

Today, the car wouldn't even stay running, it would just sputter and stall.

So I don't know haha

TehMonkay · 08-30-2009, 09:25 AM

When you say it clears up the next day when you rev the piss out of it, it sounds like there may be way too much fuel. Have the injectors been cleaned?

NoDOHC · 08-30-2009, 02:31 PM

Tehmonkey, Leaking injectors is the best theory I have heard yet. Dirt in the fuel system may do this too.

Whizbang · 08-30-2009, 03:36 PM

reminds me of how my FB is acting only it will start and run just dandy. Just hates "driving"

jerd_hambone · 08-30-2009, 07:14 PM

It may be flooding, it does run rather rich, but it only does it sometimes, and it has no problems hot or cold starting.

Just has alot of problems driving at completely random points in time

08-27-2009, 10:44 PM	#3
dudemaaan Rotary Fanatic Join Date: Mar 2008 Location: Brenham, TX iTrader: (4) Posts: 335 Rep Power: 17	how modified is the car? My car does it sometimes too, i have minimized it by tuning, but it still exists. I read an article explaining that the design of the rotary allows exhaust gases to mix with the fresh mixture in certain situations and it causes a misfire and results in the bucking. The technical name is 3:3 ignition mis-fire. here's a link to the pdf. http://foxed.ca/rx7manual/manuals/RE...amoto-1981.pdf __________________ 500+ HP thanks to: Fast reacting IAT sensor thread! Mechanical Pre-turbo Water Injection Thread Dual Stock fuel pumps Thread T2 differential swap!

08-28-2009, 10:33 PM	#10
NoDOHC The quest for more torque Join Date: Sep 2008 Location: Sheboygan, Wisconsin iTrader: (1) Posts: 855 Rep Power: 17	My '91 likes premium more than regular. My old '86 never cared at all, with the 8.2:1 rotors it really doesn't car now. On the original topic: I had my '86 buck and shake once, but it was because I had the leading and trailing plugs connected backwards. Obviously, that doesn't come and go. I am guessing that you have a bad connection or a fueling issue (loose sock or something). This is an interresting problem, keep us posted. __________________ 1986 GXL ('87 4-port NA - Haltech E8, LS2 Coils. Defined Autoworks Headers, Dual 2.5" Exhaust (Dual Superflow, dBX mufflers) 1991 Coupe (KYB AGX Shocks, Eibach lowering springs, RB exhaust, Stock and Automatic) Last edited by NoDOHC; 08-28-2009 at 10:42 PM.. Reason: More info

08-30-2009, 09:25 AM	#12
TehMonkay Rotary Fanatic Join Date: Apr 2008 Location: Louisville, KY iTrader: (0) Posts: 302 Rep Power: 17	When you say it clears up the next day when you rev the piss out of it, it sounds like there may be way too much fuel. Have the injectors been cleaned? __________________ My car blows up everytime I start it, it's rotary

08-30-2009, 02:31 PM	#13
NoDOHC The quest for more torque Join Date: Sep 2008 Location: Sheboygan, Wisconsin iTrader: (1) Posts: 855 Rep Power: 17	Tehmonkey, Leaking injectors is the best theory I have heard yet. Dirt in the fuel system may do this too. __________________ 1986 GXL ('87 4-port NA - Haltech E8, LS2 Coils. Defined Autoworks Headers, Dual 2.5" Exhaust (Dual Superflow, dBX mufflers) 1991 Coupe (KYB AGX Shocks, Eibach lowering springs, RB exhaust, Stock and Automatic)

08-30-2009, 03:36 PM	#14
Whizbang Respecognize! Join Date: Jul 2008 Location: Δx = ħ/2Δp iTrader: (5) Posts: 3,190 Rep Power: 20	reminds me of how my FB is acting only it will start and run just dandy. Just hates "driving" __________________ For current updates and event coverage check out Follow on Twitter! @WhizbangRally Whizbang Rally's Webpage \| Facebook

08-28-2009, 10:53 AM	#5
JL1RX7 Rotary Fanatic Join Date: Feb 2008 Location: Front Royal, VA iTrader: (1) Posts: 487 Rep Power: 17	Check all of your grounds. I know if they are bad or corroded that can lead the car to do some weird stuff.

08-28-2009, 02:32 PM	#8
JL1RX7 Rotary Fanatic Join Date: Feb 2008 Location: Front Royal, VA iTrader: (1) Posts: 487 Rep Power: 17	With NA you can use cheap stuff. 87 octane works just fine. Also did you check you battery cables and spark plug wires?