ecm woes?
Thread Starter
Racer
Joined: May 2006
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From: Laredo Tx
I'll get either a code 21 or 22. Sometimes a code 13 too. What drives me insane is that some days the car turns on fine and stumbles and on other days it wont start at all. Theres no current at the fuel pump fuse, I would remove and install the fuse and at timez it turns on. Any ideas?
Le Mans Master
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
Year?
Do you have a factory service manual for it yet?
Do you have a factory service manual for it yet?
Thread Starter
Racer
Joined: May 2006
Posts: 358
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From: Laredo Tx
Burning Brakes
Joined: May 2011
Posts: 838
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From: Louisville Ky
if no spare hands, remove fuse, wedge ligt termnals in or put in short paper clips and test those.
Thread Starter
Racer
Joined: May 2006
Posts: 358
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From: Laredo Tx
how are you checking it? with key on, not in start, the fuse is energized for 2 secs only. wedge a test light probe in each fuse end -don't have to remove it- and have someone turn key on.
if no spare hands, remove fuse, wedge ligt termnals in or put in short paper clips and test those.
if no spare hands, remove fuse, wedge ligt termnals in or put in short paper clips and test those.
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Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
DOES THE ENGINE CRANK? "does not turn on" is not descriptive.
if you get 2 secs of light, that is normal for key ON. if you turn key to start the FP relay will stay on, then you get pressure at rails.
code 21 is TPS, unrelated to FP and pressure.
first -or next- how have you verifed no pressure at rails?
there should be SOME fuel at rails if FP is cycling on for the 2 secs. so that is your first problem to resolve. listen for FP to come on when you turn key on. you can cycle it many times to be sure what you are hearing.
I would verify fuel filter too, but it generally allows some pressure unless totally clogged, which I have never seen.
if what you say is accurate, sounds as if FP is not working. go to "cranks but will not run" chart a-3.
Thread Starter
Racer
Joined: May 2006
Posts: 358
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From: Laredo Tx
Ok determined it does have current at the fp fuse and some pressure at the fuel rail. Im gonna get a fuel pressure gauge later on today. The car cranks but will not start. I will check the chart.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
an educated opinion is, engine should start, but maybe not run, with 20 lbs pressure in fuel rails. should be 36 min, but we are concerned about starting, right now.
chart a 3 focuses on spark first.
DOES THE TACH REACT WHEN CRANKING? IF so you should be getting reference pulses to ecm.
also, check fuses to FI, air bag, ecm, etc.
can check for spark by grounding a plug wire at the plug. if no spark you go to chart c-4.
others will post, but I will try to watch progress of this. some more advice: read and reply to every suggestion offered or you will miss a possible clue. most people condense the fsm charts to a quick check, from experience.
saludos, joe
Thread Starter
Racer
Joined: May 2006
Posts: 358
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From: Laredo Tx
Actually my tach isnt working and I know its not the cluster because I have replaced it. My distributor might be bad, which I am going to replace. You think this might have something to do with it?
Gracias
Gracias
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
chiste.distr can be rebuilt cheaper than replaced. IF it needs it. I just did mine last week.
the ecm needs reference pulses from dist purple/white stripe wire to fire injectors. will not run without that.
when did you notice that tach did not work? because it may be failing now for some reason OTHER THAN ref pulses. there are testers that read tach during diagnostics but I have never used one.
look at the chart and it will lead to spark or fuel. if problem is in HEI it will generally be ICM or pickup coil. both are $20-$25.
chart a-3, item 1, asks if tach shows RPM. at crank spd it will barely bounce. if no rpm, do the spark check.
did you check fuses? air bag uses that fuse for ecm power, I think.
saludos, joe