Peejay56

Hi everyone - Pete Jackson from the UK.

Can anyone help please?

My eldest son has recently imported a 2007 Grabber Orange 4.6 GT, 5-speed manual. The car is great but we have a problem with the throttle.

The throttle response is way, way too sensitive - setting off in first gear is difficult - too little throttle and the car bogs down. If you then apply the minutest amount of throttle the car takes off violently spinning the rear wheels. As far as I'm aware the car is completely standard and not tuned in any way.

I'm going to clean the throttle body as it does look dirty on closed throttle, so behind must be bad also.

Question is - does this seem like a dirty throttle body issue?

There's lots of information regarding the reset/learning of the various electronic control modules when reconnecting the battery, somewhat confusing.

What is the correct method to reset the throttle when the battery is reconnected please?

Thanks in anticipation,

Pete.

Dino Dino Bambino

Where in Cheshire are you situated? I was born in Sale just South of Manchester but I'm living in Cyprus.
Anyway, it would indeed be a good idea to remove the throttle body and clean it thoroughly inside out. You could also gently clean the MAF sensor element with a cotton wool bud (Q-tip) that was dipped into a non-chlorinated parts cleaner. Disconnect the negative battery cable before you start and reconnect it after you finish. That'll allow enough time to reset the ECU.
Turn the ignition key to the ON position and with the engine off, slowly and steadily depress the accelerator pedal until it hits the floor, and release it in similar fashion. Repeat this procedure twice. This will reset the throttle position and accelerator pedal position sensors.
Then start the engine from cold and allow it to idle until the temp. gauge reaches normal operating temp. Once there, switch on either the AC or the window defroster and allow the engine to idle for a further two minutes. This will complete the idle reset procedure and you'll be good to go.
If the throttle pedal is still too touchy it's possible that the throttle position sensor is faulty and requires replacement.

GT Nate

It's all throttle by wire, the throttle pedal is bolted to the firewall and has one connection. and 3 bolts. You can remove it, the connector and take it out. Then there's about 5 hex screws holding the side plate on. You can undo those and expose the connections to the throttle (they all appear to be brass or copper). Once exposed you can clean the contact surfaces which should help the signal get through cleaner. Then just put it back in the car and do the reset procedure.

Derf00

Does the car have any modifications to it like a tune? Do you know what gear ratio is in the back?

Peejay56

As far as I can tell the car is completely standard with no modifications, no CAI nothing - I can't be 100% sure it doesn't have a tune.

I can't check the rear axle code to get the ratio as the car is at my son's house - not nearby.

Only thing I can say at 70 mph in 5th gear the engine is doing approximately 2,000 RPM.

(For Dino Dino I live in Tarporley)

Pete.

JimC

Often a touchy throttle is a result of a tune that was set up to increase the throttle response. Even without a CAI the car could have a tune on it.

Dino Dino Bambino

If the engine otherwise runs perfectly and has an even idle, I'd say the ECU has been tuned. You'll soon get used to the sharp throttle response and learn how to modulate the pedal while slipping the clutch on take off.
Your rear axle ratio is 3.31 and with stock sized tyres (764 revs/mile), 4th gear pulls 23.7mph/1000rpm and 5th gear pulls 34.9mph/1000rpm, so it looks like your speedo is bang on.