No Go - sputters when pedal goes to the metal

Fiatracertracer · Post by **Fiatracertracer** » Wed Sep 16, 2015 5:02 am

My fiat sputters when I press the pedal all the way down.

Feels like it is starving for fuel.

It responds well and runs great when the pedal is slowly depressed.

It doesn't like a quick press down to the floor board and when the pedal is kept in down in that posisition for a long period of time.

It has a new fuel pump and filter and I've run many bottles of fuel injector cleaner through the tank, which has smoothed out the shake had at idle.

Has anyone ever experienced this?

76was124 · Post by **76was124** » Wed Sep 16, 2015 6:10 am

Have you checked the AFM flap, AFM resistance, and your timing?

Fiatracertracer · Post by **Fiatracertracer** » Wed Sep 16, 2015 6:24 am

No I have not.

Reading through some material on the net now.... I was wondering if there was a quick solution to the problem from anyone who had experienced this already. Not sure how to check the flap or resistance.

bradartigue · Post by **bradartigue** » Wed Sep 16, 2015 8:46 am

Sounds like a sticking/slow flap in the AFM.

When you press the pedal all the way down a device called a throttle position sensor (black thing on the throttle) tells the ECU that you are "wide open" and the injectors go full force. When the AFM flap (which measures the air coming in) is sticking the air the engine needs won't come in fast enough and it bogs down.

This is very easy to check, you unbolt the AFM from the air filter house and check the operation of the flap. If it moves very smooth and easily then the flap isn't the issue and you have to start testing things with a voltmeter.

Fiatracertracer · Post by **Fiatracertracer** » Wed Sep 16, 2015 11:56 am

I will have to check it when I get home.

Fiatracertracer · Post by **Fiatracertracer** » Wed Sep 16, 2015 1:18 pm

Is there a "How To" somewhere on how to make adjustments to tune to the AFM?

narfire · Post by **narfire** » Wed Sep 16, 2015 2:27 pm

Fiatracertracer wrote:Is there a "How To" somewhere on how to make adjustments to tune to the AFM?

As mentioned above , if the flap is sticky, then gently sand some material away to allow the flap to move freely.
The afm is sealed with the black plastic cover. This can come off as a last resort and some have moved the pins that run on the strip 1/2 a mm or so. the pins are then are running on clean material. The pins spend a lot of their life at the beginning of the strip and that area can sometimes give the description you have described.
Best to rule out all other potential issues first though.

bradartigue · Post by **bradartigue** » Wed Sep 16, 2015 3:06 pm

Fiatracertracer wrote:Is there a "How To" somewhere on how to make adjustments to tune to the AFM?

There are no adjustments. You do not tune the AFM. You do not tune fuel injection, you make sure everything works, and you leave it alone. It cannot be chipped or fooled.

Download some guides, you should start by reading and not working.

76was124 · Post by **76was124** » Wed Sep 16, 2015 7:33 pm

bradartigue wrote:
Download some guides.

Highly recommend the the one by Mr. Artigue ! http://www.artigue.com/fiatcontent/Arti ... 124_MM.pdf

KevAndAndi · Post by **KevAndAndi** » Thu Sep 17, 2015 10:53 am

My advice to anyone who acquires a fuel-injected Spider is: Do not pass Go. Do not collect $200. Instead, immediately send your AFM off to Fuel Injection Corp. in Tracy, CA, and for $200 they will refurbish it and return it to you looking and operating like a brand new part. Best money I ever spent on the car. It is an important component and having it renewed will save you many headaches down the road.

Just my two cents.

bradartigue · Post by **bradartigue** » Fri Sep 18, 2015 6:15 pm

KevAndAndi wrote:My advice to anyone who acquires a fuel-injected Spider is: Do not pass Go. Do not collect $200. Instead, immediately send your AFM off to Fuel Injection Corp. in Tracy, CA, and for $200 they will refurbish it and return it to you looking and operating like a brand new part. Best money I ever spent on the car. It is an important component and having it renewed will save you many headaches down the road.

Just my two cents.

Within some reason I agree. I look at it like this: the FI cars are for people who don't like to tinker, because there isn't much to tinker with. Get a voltmeter and test everything, and if it passes, great, if not, refurb the AFM and replace the senders, get the injectors cleaned, and leave it alone for 10 years. The system lasts a long, long, long time when renewed.

Fiatracertracer · Post by **Fiatracertracer** » Sat Sep 19, 2015 5:29 am

Brad,

There's an incredible amount of information in these manuals and I appreciate all the work you've done, it has helped me a lot.

Thank you.

Fiatracertracer · Post by **Fiatracertracer** » Sat Sep 19, 2015 8:26 am

Fixed.

It was a vacuum hose, it looked good from the outside but it leaked around the spring clamp.

bradartigue · Post by **bradartigue** » Mon Sep 21, 2015 9:49 pm

Fiatracertracer wrote:Brad,

There's an incredible amount of information in these manuals and I appreciate all the work you've done, it has helped me a lot.

Thank you.

Editing about 300 more as I type this. Never start writing books. You never stop.

No Go - sputters when pedal goes to the metal

No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal

Re: No Go - sputters when pedal goes to the metal