DUDE!!!!! Where's my acceleration???

**gaskett** · 31-03-2006, 09:37 AM

I Have A Slight Problem With The Old Girl (sx 91, Ae92 Hatch) Running A Little Rough, Surging And Sluttering Through 2000rpm And 3500 Rpm Usually In 1st And 2nd Gears With Engine Warm. When I Bought The Car, It Had Had A Rebuilt 4age. I Took It Back To Have It Serviced From The Guy Who Built The Engine And Knew The Previous Owner, So I Figured He Knows The Car He Can Tell Me What The Problem Is.

He Said The Surging And Flucuating Idle Could Be The Result Of Poor Fuel Which The Previous Owner Was Notorious For Using (ron 91) He Did A Quick Investigation Due To My Time Constraint And Also Said It Could Be, Now I'm Not Too Sure About This, "a Breather Cable????" I Think Thats What He Said, Any Way He Said It Was Cheap To Replace (cable Runs Between The Radiator And Engine ) Any Ideas Of Other Reasons Besides Bad Fuel And This Cable? I'm Running 98 Ron Fuel Now On His Suggestion As He Was 955 Certian Thats What Is Causing The Issue.

It Idles Fine Some Times At 1000 Rpm (i Know Too High) But It Was Bouncing Between 600 And 900 Rpm Up And Down At The Lights So He Increased It Temporarally

It Runs Fine Once Through The Gears And On The Freeway, Like A Dream.

**mullett** · 31-03-2006, 09:44 AM

Wow man, chill with the capitals, that must have taken nearly as long to type as it did to read

Other than that, it could be those things, it could also be a worn out rotor cap, bad spark leads, bad spark plugs, blocked injectors, dodgy fuel pump...etc

RM.

**Dom-AE71** · 31-03-2006, 09:48 AM

even when your driving is the accelerator a little touchy??

i could be a faulty Throttle Position Sensor

**stradlater** · 31-03-2006, 09:48 AM

First things first, that was damn hard to read with every word capitalized....

Secondly - It could be any number of things, but I'd be more inclined to this it is electronics of some sort. Like your idle stepper motor playing up, of the ECU doing funny things with the timing/fuel because of a bad/dodgy sensor of some sort... Not that I'm inherently an EFI guy, but I'd be checking things like your O2 sensor(s) , air flow meters or sensors (depending what you have) and maybe even go so far as to check for any error codes on the ECU.

Sounds like it MIGHT have been bad fuel that has damaged the sensors, but I'd say that using decent fuel and a new set of spark plugs now would eliminate that as being the sole reason for the problem (bad running fuel).

**gaskett** · 31-03-2006, 09:50 AM

As for the capitals the caps lock was on and i hadn't noticed. website converted everything back to caps on each word. Weird!! Accerator is fine once car is through the gears its just the changing up it gerks through 2000 to 3000-500 rpm. got me baffled. some days are also worse than others. Timing was also fine.

**gaskett** · 31-03-2006, 09:53 AM

The plugs were replaced and leads during the rebuild. It has improved after running two full tanks of 98 through it on the suggestion of the mechanic. i guess this is why I also only run 98 in my scooby doo also. saves sh$t like this happening to that also.

**stradlater** · 31-03-2006, 09:55 AM

Well, if the 98 octane is assisting it, try pulling the positive terminal off your battery for a few minutes, to reset the ECU and then hopefully it might forget the corupted settings it was having from the bad fuel.

**gaskett** · 31-03-2006, 09:59 AM

now you mention it, I did need a jump start the scond day I had the car. Could this have been an issue? will try your tip about the positive terminal.

**stradlater** · 31-03-2006, 10:01 AM

I wouldn't have thought so, given the fact that a flat battery would facilitate the ECU forgetting any error conditions. If anything it would have worked in your favour.

**Jorrs** · 31-03-2006, 04:36 PM

just a simple thing, but have u taken the throttle body of and cleaned it up, i remember had same thing in old celica opened up throttle body and was black and had so much shit in it, seemed to clear the idle up.

**Draven** · 31-03-2006, 04:40 PM

a 4a-ge does not need 98 to run - in fact you really sholdn't notice any difference apart from placebo, so I'd be looking for an underlying problem that the 98 is hiding.

**mullett** · 31-03-2006, 07:41 PM

If you needed to get it jump started, and you didn't use EFI leads, there's a (small) chance that you might have stuffed a sensor or burnt something in the ECU. If you've got a spare ECU or know someone with one, swap them over and see how it goes...

RM.

**EldarO** · 01-04-2006, 05:33 PM

drain the fuel, that way you get rid of the old shit permanantly.

replace your fuel filters, that'll clear everything up.

take the positive lead off the battery, and put your lights on, and put your foot on the brake for a few minutes, this will completely drain your car, and reset your ECU.

i had to do this when mine didnt reset after i just took it off for a few minutes.

Eldar.O.