New build won't fire.
Thread Starter
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Joined: Oct 2014
Posts: 70
From: Kansas City, Kansas
New build won't fire.
I've finally finished my 383 for my 1994 camaro and cant get it to start. I have over 45 psi fuel pressure at the rails and a brand new summit opti. its throwing no codes and the spark plugs are dry after many attempts to start the car.. after checking with a noid light, I don't think im getting pulse to the injectors. The VATS had been bypassed with a resister installed prior to my pcm4less tune (I now have the vats tuned out supposedly but the car wont crank without the resistor still???) Any info you guys have would be great
EDIT: these are brand new 30 lbs/hr accel injectors (150830 part number)
EDIT: these are brand new 30 lbs/hr accel injectors (150830 part number)
Last edited by thenewkid; Aug 9, 2018 at 07:25 PM.
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Joined: Nov 1998
Posts: 71,098
From: Hell was full so they sent me to NJ
Re: New build won't fire.
Do you have spark at the coil wire? .... at the plugs?
Could be the Opti. Lack of the low res cam position signal from the Opti can prevent spark and injector pulses. In theory you would get DTC 16. But that code can only set if the PCM sees a lot of high resolution pulses, without seeing a low res pulse. If there is a high res pulse, it takes an extended, continuous cranking to accumulate enough pulses to set DTC 16. And if there is no high res pulse at all, no code.
Use Shoebox's test procedure:
4th Gen LT1 F-body Tech Articles
A quick check..... when the starter is cranking the engine, does the tach needle move upwards to 300 RPM or so?
If the test confirms you have signals from the Opti, and they are reaching the PCM, and the PCM is sending the “fire” signal to the ICM, we can try a few other checks.
Could be the Opti. Lack of the low res cam position signal from the Opti can prevent spark and injector pulses. In theory you would get DTC 16. But that code can only set if the PCM sees a lot of high resolution pulses, without seeing a low res pulse. If there is a high res pulse, it takes an extended, continuous cranking to accumulate enough pulses to set DTC 16. And if there is no high res pulse at all, no code.
Use Shoebox's test procedure:
4th Gen LT1 F-body Tech Articles
A quick check..... when the starter is cranking the engine, does the tach needle move upwards to 300 RPM or so?
If the test confirms you have signals from the Opti, and they are reaching the PCM, and the PCM is sending the “fire” signal to the ICM, we can try a few other checks.
Thread Starter
Registered User
Joined: Oct 2014
Posts: 70
From: Kansas City, Kansas
Re: New build won't fire.
I haven't checked for spark yet... my battery died shortly before I posted yesterday, but I was able to charge it enough to confirm the tach doesn't move when cranking. It is starting to sound like the opti is the culprit to me
Administrator
Joined: Nov 1998
Posts: 71,098
From: Hell was full so they sent me to NJ
Re: New build won't fire.
Do the complete test outlined by Shoebox.
Are you sure the connector is tight into the Opti, and tight on the gray one on the passenger side of the intake manifold?
http://shbox.com/1/evap_sol.jpg
Are you sure the connector is tight into the Opti, and tight on the gray one on the passenger side of the intake manifold?
http://shbox.com/1/evap_sol.jpg
Thread Starter
Registered User
Joined: Oct 2014
Posts: 70
From: Kansas City, Kansas
Re: New build won't fire.
Its hard to tell. I thought it looked loose on the opti side yesterday... I can still see the blue boot around the connector but it feels like its on there. Also I'm not sure if it makes any difference but the little harness extension is from my obd1/ early style opti, I shouldn't need a different connector for my obd2 style opti right?
Registered User
Joined: May 1999
Posts: 215
From: St.Louis.Mo,USA
Re: New build won't fire.
The connector for 93-94 is the same, 95-97 connector is longer. If you're using a 93-94 opti harness, on a 95-97opti, it's not making connection at the opti.
If you made a signature with, your car year, and mods done to it, it would help people, help you.
If you made a signature with, your car year, and mods done to it, it would help people, help you.
Last edited by Pullngz; Aug 10, 2018 at 07:59 PM.
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Posts: 71,098
From: Hell was full so they sent me to NJ
Thread Starter
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Joined: Oct 2014
Posts: 70
From: Kansas City, Kansas
Re: New build won't fire.
I am truly sorry. Fred has also got on me about this... I tried making a sig a couple years back and for whatever reason it wouldn't work at that time and I gave up on it. So you really figure its just that extension piece not making contact? That seem like way too easy of a fix from my experience with this car haha
Last edited by thenewkid; Aug 11, 2018 at 01:20 AM.
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Joined: May 1999
Posts: 215
From: St.Louis.Mo,USA
Re: New build won't fire.
That's definitely it, if you are using a non vented opti(spline drive) harness, and a newer vented(cam pin drive) opti. The 93=94 spline drive plastic connector, was only 1/2" long where it plugged into the opti. The 95-97 is more like 1 1/2" long.
Dimensions are from memory, but moral of the story is, you definitely need a new harness if you converted from a spline drive to a pin drive opti. Look at the link Fred provided above, and compare it to your harness, it should be very obvious they are not the same.
Than post a video of it running! I would love to hear it.
Dimensions are from memory, but moral of the story is, you definitely need a new harness if you converted from a spline drive to a pin drive opti. Look at the link Fred provided above, and compare it to your harness, it should be very obvious they are not the same.
Than post a video of it running! I would love to hear it.
Thread Starter
Registered User
Joined: Oct 2014
Posts: 70
From: Kansas City, Kansas
Re: New build won't fire.
That's definitely it, if you are using a non vented opti(spline drive) harness, and a newer vented(cam pin drive) opti.the 93=94 spline drive plastic connector, was only 1/2" long where it plugged into the opti. The 95-97 is more like 1 1/2" long.
Dimensions are from memory, but moral of the story is, you definitely need a new harness if you converted from a spline drive to a pin drive opti. Look at the link Fred provided above, and compare it to your harness, it should be very obvious they are not the same.
Than post a video of it running! I would love to hear it.
Dimensions are from memory, but moral of the story is, you definitely need a new harness if you converted from a spline drive to a pin drive opti. Look at the link Fred provided above, and compare it to your harness, it should be very obvious they are not the same.
Than post a video of it running! I would love to hear it.
Administrator
Joined: Nov 1998
Posts: 71,098
From: Hell was full so they sent me to NJ
Re: New build won't fire.
The link in post #8 is the longer 95-97.
This is the shorter 93/94:
https://www.eficonnection.com/home/p...ess-non-vented
If you happen to have an LT1 from a 92 Corvette, it gets even more confusing, because they used a 5-wire cable, due to an added shielding wire to prevent any radio interference that wouldn’t be stopped by the fiberglass body.
This is the shorter 93/94:
https://www.eficonnection.com/home/p...ess-non-vented
If you happen to have an LT1 from a 92 Corvette, it gets even more confusing, because they used a 5-wire cable, due to an added shielding wire to prevent any radio interference that wouldn’t be stopped by the fiberglass body.
Thread Starter
Registered User
Joined: Oct 2014
Posts: 70
From: Kansas City, Kansas
Re: New build won't fire.
Ok so I got the new wiring in and now when I try to start it the starter is just getting stuck halfway on the flex plate and wont come off unless I go underneath and push it back (the gear)…. This whole thing is driving me crazy
. battery is charged. not sure if the starter is toast or if its not engaging the flex plate correctly. These don't look like the original starter bolts.. its a summit starter that came with the car in 2011 and the flex plate is a new 153 tooth from eagle. No metal shavings or damages, it just gets stuck and keeps trying to turn but wont. Even when I turn the motor by hand a little it still does it.
. battery is charged. not sure if the starter is toast or if its not engaging the flex plate correctly. These don't look like the original starter bolts.. its a summit starter that came with the car in 2011 and the flex plate is a new 153 tooth from eagle. No metal shavings or damages, it just gets stuck and keeps trying to turn but wont. Even when I turn the motor by hand a little it still does it.
Registered User
Joined: May 1999
Posts: 215
From: St.Louis.Mo,USA
Re: New build won't fire.
Was it cranking the engine over alright, before? This is the first time you have mentioned this issue.
If it was cranking(while not firing) before, seems like you have a starter issue now. Possibly the spring is broken? Sounds like the solenoid is engaging, but the spring not returning it back.
If it was cranking(while not firing) before, seems like you have a starter issue now. Possibly the spring is broken? Sounds like the solenoid is engaging, but the spring not returning it back.
Thread Starter
Registered User
Joined: Oct 2014
Posts: 70
From: Kansas City, Kansas
Re: New build won't fire.
I took the starter and battery to the local autofarts and found out the battery is at 7% so its charging now... how was I able to get 12v with my multimeter if it was that low?
The engine cranked fine before.
The engine cranked fine before.
Last edited by thenewkid; Aug 16, 2018 at 06:35 PM.