Fiat 1.6 2001 primary.

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Re: Fiat 1.6 2001 primary.

Postby hbr » Sat Apr 28, 2012 7:25 pm

Hello, i did a flow test and the pump deliverd in 30 seconds 1 liter fuel. Don't have the specs for that.
I also did the primary test with snap throttle, and i measured the current from the pump with engine off and let it turn for a while.
Attachments
Fiat pump engine off.psdata
(1.16 MiB) Downloaded 217 times
Fiat Wot 2.psdata
(1.82 MiB) Downloaded 242 times
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Re: Fiat 1.6 2001 primary.

Postby ScannerDanner » Sat Apr 28, 2012 8:03 pm

I still say it looks like you have an ignition problem. Especially on the green trace, but I am also seeing it on the yellow trace on occasion. What you are looking at is NOT lean misfiring. Attached is what a typical lean misfire looks like on a snap throttle test.
What are your fuel trim numbers? I'm just asking to make sure the engine isn't running rich as this could cause fuel fouling of the spark plugs and also give you the waveform you are seeing in the primary.
Attachments
97 3100 Lumina (lean misfire) snap.jpg
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Re: Fiat 1.6 2001 primary.

Postby Robski » Sat Apr 28, 2012 8:55 pm

hbr

The flow is ok from my info :wink:

Move on to the ignition.

By the way a snap throttle is a jab of the pedal to WOT & straight off, in the last capture you have held it at WOT for several seconds.

Have you had the plugs out at all ?

Do you have an adjustable spark tester to force the coil full tilt ?
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Re: Fiat 1.6 2001 primary.

Postby hbr » Sat Apr 28, 2012 10:04 pm

Hello, ScannerDanner i can't see fuel trim numbers because it is not obd compliant but can only bee diagnosed by fiat specific plug. Thanks for the picture of the lean misfire, it helps me in trying to understand the waveforms, also started watching your youtube channel it is very informative.
Robski I am sorry I did not perform the test as should be, will remember this for the future. I don't have a spark adjuster but next week they will supply me with another coil. Plugs have been out, they don't look bad, but I think with the coil I will replace them. When I have new information I will post it here.
Learning a lot out here so thanks to all of you, also sorry if my English writing isn't always very good.
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Re: Fiat 1.6 2001 primary.

Postby Robski » Sat Apr 28, 2012 10:41 pm

hbr

your English is very good thank you very much i understand you perfectly.

No problem with the snap throttle i was just letting you know what one is for future reference as it shows several things up in the cylinder.

I'm pretty sure the coil & leads will sort this, i was drawn to the fuel pressure at the start as you said the O2 was low at WOT on a road test & the lean code.

Post your fix captures when you're done & save them for you're future reference.
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Re: Fiat 1.6 2001 primary.

Postby hbr » Thu May 03, 2012 9:19 pm

Hello, put on another coil with leads and new spark plugs. It runs better but still not 100%.
I attatched the psdata for you to have a look, the complete misfire is gone but i think it is still rough.
Attachments
Fiat new coil.psdata
(1.58 MiB) Downloaded 232 times
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Re: Fiat 1.6 2001 primary.

Postby Fat Freddy » Fri May 04, 2012 5:48 am

Hi hbr

I agree with Scannerdanner, in your first capture it looks like the spark is tracking to ground.
And just a tip to help when doing ignition captures, try keeping the sample rate at 1MSsec or you lose too much info - firing voltage.

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Re: Fiat 1.6 2001 primary.

Postby ScannerDanner » Fri May 04, 2012 3:14 pm

hbr wrote:Hello, put on another coil with leads and new spark plugs. It runs better but still not 100%.
I attatched the psdata for you to have a look, the complete misfire is gone but i think it is still rough.

That looks way better. Can you describe the "rough" symptom a little more? Rough idle? Rough under load? Maybe it is just an idle vibration? (engine mount or imbalanced cooling fan)? Maybe you also have a vacuum leak? If this is a MAF engine a vacuum leak will give you a rough idle.
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Re: Fiat 1.6 2001 primary.

Postby hbr » Fri May 04, 2012 5:20 pm

Hello, this car has a map sensor, not a maf. Sometimes I've got the idea when the car runs at idle it misfires, I will try to make a capture when it does this, maybe we can see something. Also the map reading at idle stays at 500 mbar, and I can't find any leaks.
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Re: Fiat 1.6 2001 primary.

Postby ScannerDanner » Fri May 04, 2012 5:34 pm

hbr wrote:Hello, this car has a map sensor, not a maf. Sometimes I've got the idea when the car runs at idle it misfires, I will try to make a capture when it does this, maybe we can see something. Also the map reading at idle stays at 500 mbar, and I can't find any leaks.

If it is a MAP engine (speed density) a vacuum leak will usually cause a higher than normal idle not a rough idle.
It would be great if we could see fuel trims, that sucks that we can't.
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