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Weird Throttle Response 993

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Old 01-27-2013, 04:12 PM
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eddie_993
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Default Weird Throttle Response 993

OK so I started up my car yesterday after about 1 week of not driving it and I probably let it idle for about 20 seconds before starting off. I usually let the car idle a bit more (around 1 minute) if I haven't driven for over 4-5 days but seeing as how the manual states that you should drive it to warm it up I figured might as well do that.

Off the bat I noticed that throttle response was kind of delayed and the power just wasn't there. After about 2-3 minutes of driving it I tried to accelerate hard it but it was hesitating and it seemed like it didn't want to go past around 4k. I figured I'll just drive it normally until it is fully warmed up and then try again. After probably another 5 minutes of driving the car it was fine.

I have had similar issues before when starting it cold after a few days but only between 1500 to 3000 rpm. It would feel as if the engine is revving but nothing was put down and then it would kind of kick in towards 3k. However, all of this would be gone within about 15-30 seconds and it was also when I first bought the car so I thought maybe I'm still adjusting to the 993 pedal vs my Acura.

I haven't driven the car today since I thought I should post this first. Any ideas on what could be causing this?
Old 01-27-2013, 04:18 PM
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Ed Hughes
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I'd start by cleaning your MAF. Mine developed a wicked flat spot when warm a few months after I got it-solved by pulling the MAF, with a good cleaning using CRC MAF cleaner.

When I gave mine aggressive throttle, not necessarily full throttle, it felt like it was starving for gas. When I'd let up on the pedal, it would start to come back and drive fine at crushing speeds.

O2 sensors may be on the list of culprits, perhaps.
Old 01-27-2013, 04:41 PM
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Quadcammer
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could be a wonky cylinder head temp sensor also.
Old 01-27-2013, 06:14 PM
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eddie_993
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Thanks for both of your inputs. I will try the MAF sensor cleaning first, just trying to find a good diy article on this.
Old 01-27-2013, 06:29 PM
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Quadcammer
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its easy.

1. remove air box cover...two clips
2. remove air filter...pulls out.
3. remove air box. Thats a clip that needs to be popped on the transition to the maf...flat head screwdriver works fine. Then you have a smaller hose towards the front on the bottom. loosen the clamp. Box will then come up off its mounts and out.
4. undo the electrical connector...twist off
5. undo a hose clamp holding the other side of the maf...then pull out.

carefully spray with MAF cleaner...don't use carb or brake cleaner.

assembly is reverse.
Old 01-27-2013, 06:58 PM
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eddie_993
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Thanks quadcammer. I was thinking that since I'm going to be doing that I might as well clean the throttle body too, however, the general consensus was that the VarioRam should be removed...
Old 01-27-2013, 07:13 PM
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Quadcammer
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Originally Posted by eddie_993
Thanks quadcammer. I was thinking that since I'm going to be doing that I might as well clean the throttle body too, however, the general consensus was that the VarioRam should be removed...
i have a turbo so my tb is in a different spot. as i recall, the varioram throttle body is in a convoluted spot.
Old 01-27-2013, 09:26 PM
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Stealth 993
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I would also make sure that the Varioram servos are all working, just turn on the key and the flaps will move if there is vacuum. You might want to test after a drive.

Also make sure both distributors are still synced and working.
Old 01-29-2013, 05:17 AM
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Malibu101
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One of the Distributers???
Old 01-29-2013, 11:33 AM
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Ed Hughes
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Originally Posted by Stealth 993
I would also make sure that the Varioram servos are all working, just turn on the key and the flaps will move if there is vacuum. You might want to test after a drive.

Also make sure both distributors are still synced and working.
That there is all that high-tech stuff I don't have on my '95....
Old 01-29-2013, 12:51 PM
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Stealth 993
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Originally Posted by Ed Hughes
That there is all that high-tech stuff I don't have on my '95....
There are still vacuum servos for the resonance chambers, and they make quite a bit of difference in power, also if there is a leak, the AC will not blow into the cabin. Ask me how I figured that one out?
Old 01-29-2013, 12:55 PM
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Steve Weiner-Rennsport Systems
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The first thing I'd be doing is checking the distributors to make sure the belt hasn't failed.
Old 01-29-2013, 02:24 PM
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Originally Posted by Steve Weiner-Rennsport Systems
The first thing I'd be doing is checking the distributors to make sure the belt hasn't failed.
I was going to say that too. Now it just looks like I am copying the master.
Old 01-30-2013, 07:22 PM
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eddie_993
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Thank you for all the input guys. I will check/clean the MAF sensor and also check the distributor belt.

If the distributor belt is the culprit, what would it look like? Would it just have some rips/tears or would it be completely torn?
Old 01-31-2013, 09:57 AM
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P906
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Hi,

when the twindistributor is the reason for the powerloss, then it is a broken belt in most cases...

Chris



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