Misfires and dies when hot

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blusmith
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Your car is a: 1982 124 spyder

Misfires and dies when hot

Postby blusmith » Sun Jan 29, 2017 10:24 pm

1982 spider rebuild engine and ran well for 18 months Now I'm good for about 10 miles then she turns psycho. Misfires sees at the lights and seems worse with more than 1/4 throttle When cold starts perfectly and idles perfectly when warmed up then cya le will repeat itself I have New Fuel filter; new plugs HT leads and ignition module and coil . I can hear full pump running when I switch on . Where should I look next ? Chris

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81SPIDERMATT
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Your car is a: 1981 spider 2000
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Re: Misfires and dies when hot

Postby 81SPIDERMATT » Mon Jan 30, 2017 1:03 am

attach a fuel pressure gauge to confirm pump is doing its job when it acts up ... not cold when all things are good .... you can "t" one off the cold start injector and run gauge under hood and hold it down with windshield wiper while driving ... when it starts to act up keep a close watch on the gauge ... been a while but I wanna say 30 plus pounds is what we want ... maybe someone can chime in and confirm proper pressure for the pump ... Matt

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RRoller123
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Your car is a: 1980 FI SPIDER 2000
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Re: Misfires and dies when hot

Postby RRoller123 » Mon Jan 30, 2017 4:49 am

Also check for a sticking AFM door flap. It may be doing this after it warms up under the hood.
'80 FI Spider 2000
'74 and '79 X1/9 (past)
'75 BMW R75/6
2011 Chevy Malibu (daily driver)
2010 Chevy Silverado 2500HD Ext Cab 4WD/STD BED
2002 Edgewater 175CC 80HP 4-Stroke Yamaha
2003 Jaguar XK8
2003 Jaguar XKR
2021 Jayco 22RB
2019 Bianchi Torino Bicycle

GeorgeT
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Your car is a: 1982 Fiat 124 Spider

Re: Misfires and dies when hot

Postby GeorgeT » Mon Jan 30, 2017 9:01 am

Couple of thoughts: 1. is the ignition timing correct? and 2. Is the Coolant Temperature Sensor working correctly?

blusmith
Posts: 82
Joined: Sun May 29, 2011 3:00 am
Your car is a: 1982 124 spyder

Re: Misfires and dies when hot

Postby blusmith » Mon Jan 30, 2017 1:43 pm

Thanks gentlemen Will get these things done and let you know . I forgot in my list yesterday that I also have a new Distributor cap and pick up module.
Coolant sensors gone AWOL make sense so I will check these .
I know fuel pressure "running in the garage" was a good 35psi
Has anyone ever had a new Ignition module go bad on them ?
I remember seeing an AFM fix that involved shifting the track of the "sweeper" inside the AFM - I w as wondering about that - does anyone know the link ?

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RRoller123
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Your car is a: 1980 FI SPIDER 2000
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Re: Misfires and dies when hot

Postby RRoller123 » Mon Jan 30, 2017 2:43 pm

viewtopic.php?f=9&t=20792&hilit=adjust+afm+wiper

Here is one thread about the AFM. There is a manual, and a better description somewhere regarding bending the AFM wiper, and if I can find it I will post it here. The basic idea is that you loosen the lock hardware that holds the wiper in place, push it slightly down on its vertical mounting arm, and retighten it in this new position. This forces the contact point further out onto fresh TFM (thick film resistor) material, and gets the contact point out of the wear tracks. The wear tracks are easily seen once you take the top off and look inside. Move the flap , manually, and it will be clear how the wiper sweeps across the TFM. This is surprisingly easy to do; there is no need to be intimidated by it, and it typically makes quite a difference in idle and performance across the RPM range!
Pete
'80 FI Spider 2000
'74 and '79 X1/9 (past)
'75 BMW R75/6
2011 Chevy Malibu (daily driver)
2010 Chevy Silverado 2500HD Ext Cab 4WD/STD BED
2002 Edgewater 175CC 80HP 4-Stroke Yamaha
2003 Jaguar XK8
2003 Jaguar XKR
2021 Jayco 22RB
2019 Bianchi Torino Bicycle

blusmith
Posts: 82
Joined: Sun May 29, 2011 3:00 am
Your car is a: 1982 124 spyder

Re: Misfires and dies when hot

Postby blusmith » Sun Feb 19, 2017 12:13 am

An update on this issue I found some cracked connectors ( cold start valve and temp sensor at the "Tee" ) but no improvement Had the car taken to the wizard and he thinks its a buggered Air Flow Meter. Waiting for one to be shipped from the US and will let you know Should d I have thrown out the injection and gone back to a Weber ?? Catch the next episode .

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81SPIDERMATT
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Your car is a: 1981 spider 2000
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Re: Misfires and dies when hot

Postby 81SPIDERMATT » Sun Feb 19, 2017 11:50 am

sweet you have a wizard .... cant say never had a carb on the fiat .... love my FI .... driving around here there can be thousands of feet of elevation change ... other car is an old scout ...someday it will get fuel injected also .... carb gets quirky as I head up into the hills ..... keep us posted ...Matt

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Re: Misfires and dies when hot

Postby spider2081 » Sun Feb 19, 2017 3:21 pm

Has anyone ever had a new Ignition module go bad on them ?


There have been a few posts here where people installed new ignition control modules and and experienced similar problems to yours. Some had issues with car starting when up to temp. I have had no problems with the ignition control modules manufactured by "Standard Automotive Products" Part Number LX301

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81SPIDERMATT
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Your car is a: 1981 spider 2000
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Re: Misfires and dies when hot

Postby 81SPIDERMATT » Sat Apr 01, 2017 2:00 pm

curious ... how goes the battle ?


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