ajayabb

You may remember that I was having problems with a dead pedal issue. I would drive along and the throttle would cut out and I would have to release the accelerator and push reapply pressure on the gas pedal in order to get the throttle to kick back on. It would last only a few seconds and than disappear for awhile. No faults were triggered when I took it to an Indy shop. I initially replaced the throttle body which corrected the problem for a month. Next it was on to the pedal assembly. Again, correcting the problem for a few weeks. Guess what, the problem started up again today. I am at my wits end with this problem. Any ideas. BTW. According to the Indy shop, live data did not indicate a fuel pump issue.

Skibum

Any chance it is a PSM problem?
Next time it happens try disabling it.

ajayabb

I will give it a shot. Thanks

Slamuth

Sorry to hear about the chronic issue. There's nothing more frustrating than a lingering issue that seems to evade all detection. I'm afraid I don't have any ideas or insight to offer, but I wish you the best of luck with the fix.

ajayabb

Well I just took a test drive with the PSM off and the throttle issue didn't occur so we may be on to something.

Skibum

I think the only way you will be sure is if you can get it to occur with PSM on, and then immediately switch it off and see if the issue is resolved.

ajayabb

You are right but it's gonna take some quick hands

marcus0277

How often did the issue occur before? If daily, then I'd just drive the car without PSM for a week or so. If it still didn't occur, then you might be on to something.

Unfortunately, I suspect that even if you can narrow it down to the PSM, that still leaves a whole slew of sensors & software that could be possible culprits. Not sure if your Indy or even your dealer has some sort of flight recorder or diagnostic tool that could check where a faulty signal might be coming from without taking all of the relevant sensors out and checking them individually.

Additionally... if it were PSM kicking in, wouldn't there be an indicator on the dash when it happens?

ajayabb

Thanks Shane. Yep it's a royal pain in the ***

ajayabb

It occurs daily when it acts up so it's a worthwhile experiment

ajayabb

Update to my problem Seems that we may be dealing with either a bad steering angle sensor or a glitch in the ECU. I have an appointment with the dealership to check both issues and will report back. The tech I spoke to at the dealership reports having seen this problem before. Wish me luck

Skibum

Keep us posted.
Hope it's not too expensive.

Spiffyjiff

hey ajayabb, can you elaborate on your problem? my '06S with 45k miles (about 15k track?) has had a throttle "non-response" issue twice this week. imagine being in 6th gear at 25mph and how, when you punch the gas, almost nothing happens except for a VERY slow, gradual speed/RPM climb, right? well this has happened twice to me this week, but at 25mph and in 3rd gear (or any gear for that matter - i try shifting down and up but that doesnt clear the problem). oddly, i forgot to try to put it in neutral and rev engine but will try that next time. so, anyway, the way i cleared it was to simply shut off/back on the car quickly. seemed to clear it. like nothing ever happened. and there have been no warnings or CEL's thrown.

does this sound like your issue? i am researching fuel pumps and throttle body plates now but since turning off car clears it, i'm afraid it might be electrical somehow??

ajayabb

Spiff, My issue was a complete cut out of the throttle restored when i released and depress the gas pedal Basically my car thinks that it is in a spin and cuts the throttle at random times, or if I hit a bump in the road etc. Apparently my steering angle sensor is reading something like 10 or 15 degrees off center when it should read zero degrees. As a result the ECU thinks that the car is in a spin and hence the problem. My problem occurs daily but stopped occurring if I turn off the PSM. This has been going on for me for the past 4 months. I replaced the throttle body and pedal assembly all to no avail.

RollingArt

Here is a post from RL'er stevecolletti on the 987 forum.

This is the tale of his throttle problem and fix;

" Throttle issue and resolution on my 2012 Cayman R
I'm not sure how common this is, but given how long it took to resolve, I thought I'd pass this info along to the forum.

From delivery, my 2012 Cayman R (6-speed manual and Sport Chrono), I have been having problems with the engine responding to throttle.
I thought that the problem was intermittent, but now that the car is (finally) working correctly, I know that the throttle was never working right, and that, intermittently, it would get very bad.

Intermittently:
The engine would respond as if the throttle was suddenly closed, then after a second or more it would start to accelerate. This happened most frequently on throttle tip-in, was worst at low rpm (from idle), but could also occur during throttle tip-in even while cruising at speed on a level freeway. Occasionally (on a level freeway and under constant throttle/speed), my car would go through a surging effect - on-off-on-off - that you could feel in the car as slight g changes.

All the time (prior to resolution):
The eGas throttle response was terrible. I could floor the car, remove my foot from the pedal, wait a tenth of a second or so, then the engine would rev to around 4000 RPM. The engine idled somewhat rough (RPM on the tach looked steady), had very weak torque off the line and at low RPM and suffered frequent stalls, with difficulty overcoming the drive-off assist.

Impressions:
It felt very similar to a fuel cut-off due to traction/stability control - throttle dies for about 1 1/2 seconds, then it takes off.

Things tried:
Traction/stability control - setting made no difference; weather and traction independent.
Sport mode - setting made no difference.
Fuel, 100-octane - made no difference.
Activating the cruise control (bypassing the pedal throttle sender) once the surging started - made no difference.
No blinking PSM light.

In fact, over the course of 2880 miles, nothing made a difference, nothing made it repeatable.

After 3 trips (with 3+ weeks stay) at my local dealer (McKenna), I decided to try Rusnak in Pasadena.

Brian Lewey, the Service Manager, brought their Shop Foreman out to speak to me. While standing in the service drive.... as I started to describe the various symptoms, he stopped me and gave me a list of some other symptoms that I'd encountered. He said that he believed it was probably a Brake Pedal Switch. He told me that they'd had a Spyder in some months ago, and after spending 2-3 weeks diagnosing and tracing the problem back, they'd found a 'flaky' brake pedal switch.

They replaced the switch... a $17 part - Brake Pedal Switch (PN 996-613-113-02)

The car now drives completely differently. It idles smoother, takes throttle linearly, is more responsive, has torque off the line, and no longer has the 'huge' eGas delay (it's still there, but it's better than the eGas throttle delay that came on my 2008 RS) - it now falls into the 'it can be improved', rather than 'this will end up killing me' category. According to the computer, it's even getting better mileage - while being driven harder. Also, (while I still hate the drive-off assist), it is now easy to pull into my garage.

In short, I feel the difference everywhere.

Apparently, if the switch signals that the brake pedal is being pushed, it kills throttle. Heal/toe downshifting always worked, so the interaction must be more complex than this.

Mine was the 3rd car they've had to replace this part in (2 Spyders and an R).

Too much of this stuff talks to (and worse, trusts) each other.

I hope this helps someone else not go through what I did."

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