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87 GT BackFires by FieroJosh1993
Started on: 09-19-2014 06:06 PM
Replies: 28 (285 views)
Last post by: FieroJosh1993 on 09-22-2014 07:51 PM
FieroJosh1993
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Report this Post09-19-2014 06:06 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
Hey guys, ok so got the Neutral Safety Switch dealt with.

Tried firing the car up last night and it started but then died right away, I figured the timing was off. Keep in mind I havent had this engine running yet so I cant set timing until its running. Im just trying to find the sweet spot where it will stay running for me to set the timing. So today I started moving the distributor around and found a spot where it runs for a little longer but still dies. I have triple check my wires and where they go but it doesnt want to stay running. So I move the distributor again and now it wont fire up but it back fires alot. I can't find a good spot for it. Im using ACdelco Rapid Fire Plugs, AcDelco Normal Wires, MSD Distributor and Coil.

Any help would be great.
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FieroJosh1993
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Report this Post09-19-2014 06:38 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
Ok no more back firing, I turned the Distributor some more and now the back firing is gone, car starts and then dies almost right away. I got fuel in the fuel rail and I can see any leaks of any kind. What does this sound like to you guys?? Timing still?? I cant turn the distributor anymore clockwise cause the two connectors that go into the cap wont allow it to. Going counterclockwise the car doesn't try to fire.
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Report this Post09-19-2014 06:56 PM Click Here to See the Profile for jmbishopClick Here to Email jmbishopSend a Private Message to jmbishopEdit/Delete MessageReply w/QuoteDirect Link to This Post
First, set the timing correctly with the jumper in the aldl. Second, it sounds like you might have a clogged cat but it's hard to say based on the info given.
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LornesGT
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Report this Post09-19-2014 06:58 PM Click Here to See the Profile for LornesGTSend a Private Message to LornesGTEdit/Delete MessageReply w/QuoteDirect Link to This Post
Not that I am very experienced with timing but I would bring the #1 to top dead center then pull the cap and check the rotor and see if it's aligning to the number #1 plug wire. If it far off then realign the distributor and try again. If I am wrong it's a free bump.
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FieroJosh1993
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Report this Post09-19-2014 07:06 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
Ok I will try that, I dont have a cat btw. Sorry, forgot to mention that.
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Alex.07.86GT
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Report this Post09-19-2014 07:12 PM Click Here to See the Profile for Alex.07.86GTSend a Private Message to Alex.07.86GTEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by FieroJosh1993:

Ok no more back firing, I turned the Distributor some more and now the back firing is gone, car starts and then dies almost right away. I got fuel in the fuel rail and I can see any leaks of any kind. What does this sound like to you guys?? Timing still?? I cant turn the distributor anymore clockwise cause the two connectors that go into the cap wont allow it to. Going counterclockwise the car doesn't try to fire.


Hi, having fuel and having the right fuel pressure are 2 different things. Did you check priming fuel pressure & running fuel pressure with a guage??

you need to put the rotor at TDC #1 plug. turning the distr too much will mess you up!
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FieroJosh1993
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Report this Post09-19-2014 08:32 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
Got it to TDC # 1 and it still wouldnt stay running.

No I didnt check fuel pressure. I will

[This message has been edited by FieroJosh1993 (edited 09-19-2014).]

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FieroJosh1993
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Report this Post09-19-2014 09:40 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
Ok just check fuel pressure. it should be between 34 and 40 PSI. Mine is at 40 psi with just the key to run. it goes to 45 psi when cranking. So I have plenty of fuel pressure. No leak or anything.

I think its still timing. Ok so heres what I have found in the last 5 hours of trying to get this timing right. The distributor rotates in a clockwise direction when the engine is running.

When I move the distributor counterclockwise, ( toward the passenger side ) I just get back fire and not really a start up. When I rotate it clockwise ( toward the driver side ) It starts up, but dies right away. I did notice I cant rotate the distributor any more clockwise because the Ignition Control Module wires, at the base of the distributor cap arent long enough. Could this be the issue?? I need to go further but I can't?

Also when the engine starts, if I hit the gas it will run, but as soon as I let up, it dies. I understand it sounds like a fuel issue but I got good pressure and everything is working in the fuel system, checked fuses, relays, grounds, No codes, everything. So It just leaves me to think timing.

What do you guys think.

Thanks,
Josh
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1MohrFiero
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Report this Post09-20-2014 08:32 AM Click Here to See the Profile for 1MohrFieroSend a Private Message to 1MohrFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
I have to ask since I don't see this stated anywhere. Are you sure you have a good ICM? Backfiring is common with a bad or weak one.

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FieroJosh1993
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Report this Post09-20-2014 02:18 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
its brand new, My dad and I did just crank the engine without the Ignition Coil being connected to make sure we didnt hear anything bad and to pre oil the valve train. Could this have killed the coil?? how do i know if its bad.
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FieroJosh1993
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Report this Post09-20-2014 05:41 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
switched plugs and wires, went back to OEM thinking maybe the rapid fires where the issue. Kind of sounds better but still wont stay running =(

It used to be, it would fire up then die. I messed with the timing, got the engine to TDC got the distributor rotor lined up with #1 and now the car acts like its gonna fire every crank and some times it does but it again, doesnt stay running. Am I getting closer or further away?/ i know its hard to say just from a description.

Could use some more guidance
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1MohrFiero
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Report this Post09-20-2014 06:57 PM Click Here to See the Profile for 1MohrFieroSend a Private Message to 1MohrFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yes, I have had a bad ICM take the coil with it. Acted just like you describe.
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FieroJosh1993
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Report this Post09-20-2014 07:53 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
ok i will try a new coil. Its a MSD, wouldn't think it would go bad before the engine even runs. But im at the last bit of knowledge I have with this, I either get the timing to the point it starts and then stops, or to the point of, no matter which way I turn the Distributor its to retarded, or to the point that its to advanced and It just back fires no start up. I dont get it. I dont think its the ICM just because normally if that goes bad the car wont even crank.

Guess we will see what happens.
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FieroJosh1993
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Report this Post09-20-2014 08:55 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
correct me if im wrong, but if you plug a volt meter into the Throttle Position Sensor, shouldnt it read .5 Volts when the door is closed and 4.5 to 4.9 or so Volts when you open it??

I was thinking, when i step on the gas it fires up. When i let off the gas it dies. If I already ruled out the fuel system then the only thing the gas pedal is connected to is the TPS. So I tested mine today, it starts at .9 volts which GM says is ok. As I open the TB it goes up like it should, but when I get to WOT it only read 3.5 to 3.7 volts, thats a whole Volt under what GM says it should read at WOT. Does this mean its going bad?? Could this be causing the engine to die right after start up?

[This message has been edited by FieroJosh1993 (edited 09-20-2014).]

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Report this Post09-20-2014 10:05 PM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageClick Here to Email phonedawgzSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
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FieroJosh1993
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Report this Post09-20-2014 10:39 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
ok, thats what I thought. So im still thinking timing then. Gonna have my dad help me tomorrow. Fingers crossed
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Report this Post09-21-2014 01:01 AM Click Here to See the Profile for LornesGTSend a Private Message to LornesGTEdit/Delete MessageReply w/QuoteDirect Link to This Post
Sound like you have fuel and spark ( maybe not all of plugs) but you need air also. So I would have the intake hose off the throttle body. Make sure there is air getting in the little hole on the throttle body. Maybe if you haven't tired it yet pump the throttle a little to see if it runs that way. If no air is getting in the intake air control could be stuck closed or clogged up.
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Report this Post09-21-2014 07:38 AM Click Here to See the Profile for 1MohrFieroSend a Private Message to 1MohrFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
The coil is made up of two coils. A primary and a secondary coil to get the proper spark. If one is bad you may see a spark but still not get ignition. If your spark is yellow and not blue, that may be your problem. Although, I run an MSD coil, I have heard many people complain about them failing.

[This message has been edited by 1MohrFiero (edited 09-21-2014).]

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FieroJosh1993
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Report this Post09-21-2014 10:22 AM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
Yeah I went out and got a new coil. i will check to make sure air flow is good. My dad and I are gonna start from scratch. Take out all the spark plug and the Distributor. Get the engine to TDC and then set it all up. Fingers crossed
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FieroJosh1993
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Report this Post09-21-2014 03:45 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
The car lives and it sounds amazing. Thanks to everyone for the help.

I do have another question. Ok so I was letting the car run to listen for anything weird and to let all the dirt and oil burn off. Everything sounds good and looks good btw. I did notice that after maybe 10 to 15 mins of letting it idle with a few throttle snaps the oil pressure went from 80 psi to around 45. I thought ok well the oil is just heating up. then maybe at around 20 mins it was down to 40. I shut it off then.

Is this normal. Also, I burped the coolant system according to GM and I dont hear any air, but the temp light came on. I dont have a thermostat in it just cause I was burping it. Is that why the light came on??

Thanks
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Report this Post09-21-2014 05:26 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
Oil pressure dropping to 40 is normal.

Water temp rising to turn the light on is not. You should hear a fan kick on, or there still may be air trapped in the engine around the temp sensor.

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FieroJosh1993
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Report this Post09-21-2014 07:01 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
Ok good news and bad news,

Good news is, Engine works great, oil pressure is good temp is good, timing is good.

Bad news, Was gonna take the car on its first drive. Car wouldnt go forward while it was in drive. Car shift to all gears and stays in park, but when i put it in D or 1 2 or R it does nothing. Just idles. Doesnt shift the engine doesnt change idle pitch. If I let up on the brake I just roll like I was in Neutral. Is this because of me jumping the neutral safety switch and not having it connected??

When I move the rod that goes into the Trans by hand I hear it clicking everytime it gets to a gear, but I also hear what sounds like a loose part rattling around inside the trans when i shift it by hand. Not sure if its just me or if thats how it sounds normally or if there is a problem.

I never opened the trans up, didnt even take it off the cradle. Never dropped the cradle while it was out, so not sure why its doing this. No leaks visible from trans, lines are good and tight.

I don't know if any of you will know what this could be, but ideas would be great.

Thanks all,

Josh
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Report this Post09-21-2014 07:22 PM Click Here to See the Profile for fierosoundClick Here to visit fierosound's HomePageClick Here to Email fierosoundSend a Private Message to fierosoundEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by FieroJosh1993:

The car lives and it sounds amazing. Thanks to everyone for the help.


Good to hear. (for the benefit of futures searches)

..... out of the 100 things you tried, WHAT was the solution?
Did you find the single problem that was giving you this trouble?
Or you still don't know - "it just runs now".

------------------
Calgary time/temp

3.4L Supercharged 87 GT Click me
Super Duty 4 Indy #163 Click me

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FieroJosh1993
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Report this Post09-21-2014 08:06 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
Oh good idea,

Ok so I found that the timing was just off by a lot. Not sure how much.

All I did was take out all the spark plugs and cranked the engine over by hand until I found TDC for Cylinder 1. Then I wasnt sure about the distributor, all I could find online was for doing a tune up, people saying mark the spot the rotor was last at, but mine is a new engine, never had the timing set up. I found a guy that said all you do is hook up the distributor like normal. Drop it in hook up all the plug wires, but dont plug in Cyl 1, just have it hooked up to the Distributor, then key on with the engine off. Grab the number 1 wire and hold it over a good ground, then rotate the Distributor cap until you hear the spark fire for number 1. Then plug the plug wire onto the spark plug and fire up the engine, this will give you the best timing until the motor is running.

It worked, engine ran and then I set the timing to the correct degree.

As for the trans issue, not sure what it is. but gonna keep working on it. I could use any ideas you guys have.
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FieroJosh1993
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Report this Post09-21-2014 09:28 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
could a clogged valve body make it shift but not engage properly??
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phonedawgz
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Report this Post09-22-2014 05:55 AM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageClick Here to Email phonedawgzSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
Your transmission fluid level is correct?

You remembered to put those bolts in that bolt the flex plate to the torque converter?

[This message has been edited by phonedawgz (edited 09-22-2014).]

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FieroJosh1993
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Report this Post09-22-2014 08:13 AM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
Yes fluid level is good and yes, I got the bolts on the torque converter. What do you think it could be??
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FieroJosh1993
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Report this Post09-22-2014 03:01 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
So can I take the valve body out without dropping the engine again?? Also is the valve body under the filter or is this a trans where its on the side?? What is a good cleaning agent for trans cleaning.
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FieroJosh1993
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Report this Post09-22-2014 07:51 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
Ok well I have decided to save up the money and take the car to a local trans shop I trust. Owner knows my dad from their Air Force days and he said he would give me a good price on the work. My dad says hes a good guy and knows his stuff.

Thanks for all the help guys. I'll let you know how it turns out.
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