Whoahhhhhh, Greenie!

Well, this is scary news when you go to drive a new car for the first time. :fearful:

After reversing Greenie off the bi-level transporter (during which the driver noisily rubbed her bottom on the pavement near the rear, due to the too-acute angle of the car back there to the lot :open_mouth: :angry: ), I hopped in and went to drive her the 1/2 block or so back to my place for her first check out. However, when I put the shifter into “D”, the engine suddenly and quickly revved up to near max/redline, forcing me to hit the brake pedal hard, throw the selector into “P” and shut the ignition off. WTH??? :open_mouth: However, after I started her up again, she drove all the way back to my place uneventfully (although I made sure to park in such a way there was nothing in front of her :grimacing: ). While there, I started her up 2 or 3 more times, and everything seemed fine, still. Also, no c.e. light on. :relieved:

However, I’m gun shy to even drive Greenie again, until and unless I know what happened was just some freak isolated incident. :grimacing: Anyone have any idea what could have caused it? I never had anything like that happen with Scrapper, in my many years of owning her, or w. any other Jag (or even non-Jag). I’m wondering if sitting on the transporter for her 1,200+ mile journey to my place could have some way created the situation (or scrapping her bottom on backing her off the transport?). I did check the throttle/acc. pedal linkage, but there did not seem to be any “stickiness” to it. I did note, however, the rubber cover was missing off her accelerator pedal. I intend to ask the seller about that, as well as what happened to me and whether he ever had it happen before to him during his 2+ years of ownership. :thinking:

btw, I did discuss what happened with a neighbor of mine, who came over to check Greenie out when she arrived in our duplex complex. He seemed to think what might possibly have happened is that, all the air rushing through Greenie’s front end while sitting on the transporter during the long 2-day haul, somehow caused her T.P.S. to malfunction, falsely believing the car to be (still) going at highway speeds when I went to put the selector in “D” for the first time after arrival. That just doesn’t seem possible to me, though. :face_with_raised_eyebrow:

That…is completely fabricated. The P in TPS stands for potentiometer. If you do a quick google search, you’ll quickly learn how it works and how your neighbor is…not going to be a reliable source of information.

Your car has an OBD2 port. I suggest monitoring the readouts from:

  1. TPS
  2. MAF sensor

Something caused the car to think that the throttle was supposed to go. Other than leaky fuel injectors, I can’t really think of anything that would have caused that other than those two sensors?

1 Like

I’ll check the OBD II system, but since no check engine light is on, I would think it wouldn’t pull up any error codes, VK. :thinking: I talked to the seller since I posted that and he said the car has never done that in all the time he owned her, and was quite shocked. :open_mouth: He did say something kind of similar happened one time when he got in the car with big “muck a luck” winter/snow boots on, and apparently was pressing both pedals at the same time w/o realizing it. :blush: That explanation/scenario makes sense to me, given my big old numb feet (diabetes + lower limb lymphedema). Also, I had been used to “pedaling” an XJS the past seven years, so maybe my “feel” for the pedals in the X-300 was a bit off, in which case it will take some getting used to. :grimacing:

I didn’t say to check for codes, I said you would want to monitor the readouts from both sensors.

But I’m pretty sure you fat footed those pedals, as that would be perfect sense. The pedals are needlessly close together.

1 Like

Agreed. :blush: btw, so how do you “monitor the readouts” with an OBD II sensor? Mine just shows any codes that are up (and whether the test cycles have completed or not). :confused:

You should really consider upgrading to an ELM27 device with an app on your smartphone. They can give readouts on what the MAF sensor is seeing, oxygen sensors, fuel trims, throttle positions, coolant temps, battery voltage…some really important stuff.

The foot on the brake and throttle scenario was one that went through my mind as well.

Interesting. I’ll search around on Ebay and Amazon and see what I can find in that regard. :thinking:

Avoid the cheap eBay ELM27 devices: they’re cheap for a reason.

I plumped for the Carista app+dongle. Not cheap but it does everything I need it to.

Been using a cheapie eBay dongle for years. Never a problem.

You’re not paying a subscription, are you?

I went through three - all different brands - before biting the bullet and no, no subscription.

I have just been on a 3000klm trip around the South Island in the XJR, I had a Vgate code reader hooked up while the wife was driving so that I could read the long and short term fuel trims.
It’s a basic unit but does read some codes, i was quite happy to see the trims were reacting to throttle activations quite quickly.
Also I was happy with the 24+ imp MPG average fuel economy over the trip.

1 Like