North American Turbocoupe Organization



stuttering and backfiring
jabobia Offline
Member
#1
hey everyone - first post here on nato but maybe someones seen me on turboford [Image: biggrin.gif]

i posted this on turboford but noone could figure it out so i thought id try here

once i get to 5k in any gear it feels like it hit a wall and struggle to pull to 6k and once i upshift ill get a backfire and the car will stutter like a cylinder is dead but still boost up to 18psi...if i idle down while its stuttering the engine may die or idle rough with 9" of vac. gradually smoothing out and pulling 16" again

it will only do this if i am running over say 15psi...and once in a good while it wont do it and its great to pull to 6k with 18psi and bang gears...but only once in a good while usually it will stutter

it isnt affected by temperature(engine or air) b.p. or humidity

i have no vac. leaks from the tree, my vam hose is not collapsing, i have checked the wires cleaned the cap and rotor and they are excellent...ive tried two sets of plugs(motorcrafts and ngks)

and again it only happens over 14-15psi over 5k and sometimes it will clear up say once a week

stock 87 t/c 5spd k&n and home-made b/c 12* ign. timing(spout d/c)...p.o. installed holley 190lph pump

and ideas appreciated

thanks,
james

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87 TurboCoupe - 5spd
87 Thunderbird TurboCoupe - 2.3T, T5, 3.55L - K&N, 18psi - [email protected](2.37 60')
88 Thunderbird Sport - 5.0SO, AOD, 2.73L - [email protected](2.39 60')
www.cardomain.com/id/jabobia
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Dan E Offline
Posting Freak
#2
Have you checked the Fuel Pressure at idle and under boost ?

Have you run the codes ?

Generally, backfiring would be a timing issue. Perhaps your cam is off a tooth ?

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Dan Eaves
88TC 5spd, Crower 5.5" Sportsman Rods, Short Wiseco Pistons bored .030" Over, Ported Head with Polished Combustion Chambers, Gutted & Polished Upper, Ported & Polished Lower, Polished T/B, Ported E6, SVO T3 .63AR Turbo, Bosch Bypass Valve, 3" DP w/No Cat, 2 1/2" DynoMax single cat back w/DynoMax Super Turbo Muffler, RR Cam, K&N in Fenderwell, Gillis Boost Valve, Centerforce I Clutch, Removed A/C, Polished Wheels, Polished Valve Cover, Polished Crank and W/P Pulleys, Walbro 255LPH HP Pump, Kirban Adj FPR, and the DAMN Heater Core is new too !

NATO MEMBER (Vice Chairman...if it's a vice...I deal with it)

[This message has been edited by Dan E (edited 08-11-2003).]
Dan Eaves
88TC 5spd Vermillion Red, Polished...everything...
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jabobia Offline
Member
#3
thanks for the reply [Image: biggrin.gif]

I have no way of checking the fuel pressure. I'll try using a tire gauge to check idle pressure, lol.

2 weeks ago i had no codes...i will pull codes now and reply again

i have checked the cam timing 5 times and even tried it one tooth each way...the problem did go away if i jumped it one tooth advanced and got worse one tooth retarded...ive checked the indexing and marks on the cam and crank twice to make sure theyre accurate so im not sure what to make of that

stay tuned for codes...

-james

------------------
87 TurboCoupe - 5spd
87 Thunderbird TurboCoupe - 2.3T, T5, 3.55L - K&N, 18psi - [email protected](2.37 60')
88 Thunderbird Sport - 5.0SO, AOD, 2.73L - [email protected](2.39 60')
www.cardomain.com/id/jabobia
jabobia.com
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William Waters Offline
Member
#4
Dan is right check fuel pressure they will backfire if fuel air mix gets too far off
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jabobia Offline
Member
#5
alright as far as codes

koeo - 11
cont - 14 58 66 72
koer - 34 77

now 58 and 66 can be explained because i disconnected the vam last week to see if maybe that was my problem

i cleared the memory and started the car up let it run and then checked my codes again

koeo - 11
cont - 72
koer - 34 77

ive already had the emissions recall done on my car so that explains the 34

could code 14 be from (dis)connecting the spout while the car was running?

someone told me code 72 was because i disconnected the battery...but i didnt between the time i cleared the memory and pulled the new codes...in fact i havent disconnected the battery since i cleared the codes 2 weeks ago

my tire gauge is screwed - do you think autozone loans fuel pressure testers?

-james
87 Thunderbird TurboCoupe - 2.3T, T5, 3.55L - K&N, 18psi - [email protected](2.37 60')
88 Thunderbird Sport - 5.0SO, AOD, 2.73L - [email protected](2.39 60')
www.cardomain.com/id/jabobia
jabobia.com
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Jeff K Offline
Administrator
#6
The CM code 14 (intermittant loss of PIP signal) can be caused by PIP going bad, but more likely is due to bad plug wires / cap / rotor giving off excessive RFI/EMI and interfering with the low voltage PIP signal. Try a new set of Motorcraft plug wires / cap / rotor, even if they have been replaced recently. What kind of plugs & plug gap are you running?

KOER 77: Operator error. Did you tap the brake pedal and give it a WOT goose to over 3000 RPM at the dynamic response code?

CM 72: Could be loosing the power to the keep alive memory (KAPWR). Check to be sure that pin 1 at the EEC is hot at all times.

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Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 20 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 02 Taurus Vulcan(wifes car)
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
05 Taurus SEL Duratec daily driver
04 Taurus Duratec (wifes car)
02 Pontiac Grand Prix GT
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
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Jeff K Offline
Administrator
#7
One more thing.... measuring fuel press at idle will tell you NOTHING, unless your pump is extrememy weak, or you have a severe restriction, etc. You have to measure pres under high demand (high boost / RPM) to really tell if you have a fuel pressure problem.

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Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 20 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 02 Taurus Vulcan(wifes car)
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
05 Taurus SEL Duratec daily driver
04 Taurus Duratec (wifes car)
02 Pontiac Grand Prix GT
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
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jabobia Offline
Member
#8
the plugs i am using are motorcraft awsf44c's and theyre the ones that were in the car when i got it last month...i swapped in ngk's but they look like they ran very hot so i put the motorcrafts back in...they look hot too but not as hot as the ngks

i have them gapped at .030"

no i didnt give it a goose [Image: redface.gif]

so pin 1 at the eec should be +12vdc at all times...key off, key on, and start?

thanks,
james

------------------
87 TurboCoupe - 5spd
87 Thunderbird TurboCoupe - 2.3T, T5, 3.55L - K&N, 18psi - [email protected](2.37 60')
88 Thunderbird Sport - 5.0SO, AOD, 2.73L - [email protected](2.39 60')
www.cardomain.com/id/jabobia
jabobia.com
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Pete D Offline
Administrator
#9
Since the stutter went away when you hooked up the Gfs laptop, have you tried hooking it up again? Out of curiosity, where/how do you hook it up and what software are you using?

What vacuum (not boost) do you get at idle when everything is running right?.
Pete Dunham


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jabobia Offline
Member
#10
yes and i have gotten some recordings of it not stuttering and of it stuttering

i am using a voltage divider and 10k pot between the (-) coil and (-) battery plugged into the mic in on the notebook

i am getting about 16-17" at idle(it may actually be 15" because my gauge sits one line toward vaccum when the engine is off...i dont know how that happened)

i use goldwave and windows sound recorder to record the ign. pulses

i just realised that the wrong plugs are in the car...im not sure why someone put them in but im off to buy some awsf32c's

-james
87 Thunderbird TurboCoupe - 2.3T, T5, 3.55L - K&N, 18psi - [email protected](2.37 60')
88 Thunderbird Sport - 5.0SO, AOD, 2.73L - [email protected](2.39 60')
www.cardomain.com/id/jabobia
jabobia.com
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