Horrible night. Car pissed. Never ran horribly like this before.

[Powertechn2]

So. I bought my car in January. I knew the original owner since about 2 years after he had the gn.
he did a frame off resto and had the car running 12's consecutively.
Car sat for 10 years. Over the years he had ran it and had told me about issues it had.
No biggie.
He sold it.
They traded it to another buddy. Neither of them knew shit about what they had, just knew it was badass.

I have it now.

I have never had a running issue like tonight before. I have put at least 200 miles on the car trying to work out bugs. Even drove it one night a few weeks ago for two hours without an issue.

The other guys said something about a backfire . I had the backfire a few times, but it would always stay running or restart quickly then be fine.

SO, of course I have been busy working. Its woodward weekend.

I take my car to the girlfriends house. First about 8 miles into the 14 mile journey The Car starts acting up. Backfiring. Then no power, then out of nowhere it's like a 12 second rocket. Then POP. back to running like shit.

Odd, never had this issue like this before.

So, barely make it to gfs house.
Trying to look car over.Didnt see anything odd. In the middle of looking under the hood I got inside the cockpit. Got out, the door slammed shit. SHIT FML. Somehow the lock was pushed down. I can see the keys. Fml. I want to set the car on fire at this point but I didn't. I really did think about it. I won't lie.


A lot of breaths. I remember I have triple a. But mancard employs itself >> > I slimjim the car with a hanger. Cool keys out. Car is not acting bitchy.

Go to drive home 2 hours later. Car is a total asshole. I make more people look at me when it backfires than ikf I was waving my handgun outside the window while honking the horn.

May I express that I have never had these issues before. I was warned about the backfire and that it runs like shit, but never never had this issue till woodward weekend.

I honestly thought about catching the bitch on fire. I won't lie... Then sanity set in. I love the car. I wanted it since before I could drive.

So.

I have a new engine side harness. I have a new ignition module, a coil, non mag tho.. I have been wanting to buy new injector set and chip, just thought I would have the time but didn't.

It seems like the ecu is dropping the reading for the cam. Is this a plausable issue?

Previous owner said it would do this once in a while but he couldn't trace the issue because at the track it rand straight. My car was set up for track runs.

I can get on it full throttle when the issue is happening and it will clear up and give it hell. I mean crazy fast as hell to the balls. Just unless you give it hell when the issue happens it will basically run like shit and stall.

If you give it hell when this is happening and then let off it will stall.
This is a too long didn't read post.

TLDR.

I lost myself somewhere too.

I am sorry. But I am lost.

Tomorrow I am attaching the fuel pressure gauge and taping it to my windshield as I saw the O2Mv drop to 090. and less at times.

I am going to swap the parts I have on hand. minus the entire engine harness and seewhat happens.

I might even swap the engine harness,although by the measurements its not a harness issue.


Shit. My luck sucks. Of course, till now car ran great.
For two hours straight even. Fml.

 

[Raeban]

Do you have a scanmaster? Also post what you know about your build in your signature so people can see what you have and help you out.

 

[TurboBuRick]

Check the cam sensor wheel.

 

[Pronto]

Is it a stock MAF? Here's some stuff to read. http://www.vortexbuicks-etc.com/engine_starts_but_does_not_run_p.htm

 

[BBCTURBO11]

A GN I had several years ago had similar symptoms ! On the way to work running great .... Out of nowhere sputters , backfires stalls . Crank no start ! I thought it was a timing chain issue. Thirty minutes later flatbed comes and drops it at the gm dealership where I'm a tech. . The car starts ! Runs great ! Damn. Check stuff out ..looks ok. On the drive home same thing a block from the house ! To make a Long story short , I found the wire to my crank sensor on the harness side was backing out of the connector ! Had on and off contact. Took four hours to find !
Good luck ! Oh ... No BBQ GN !


BBCTURBO11

 

[bogies87]

MAF

Posted from the TurboBuick.Com mobile app

 

[pacecarta]

A GN I had several years ago had similar symptoms ! On the way to work running great .... Out of nowhere sputters , backfires stalls . Crank no start ! I thought it was a timing chain issue. Thirty minutes later flatbed comes and drops it at the gm dealership where I'm a tech. . The car starts ! Runs great ! Damn. Check stuff out ..looks ok. On the drive home same thing a block from the house ! To make a Long story short , I found the wire to my crank sensor on the harness side was backing out of the connector ! Had on and off contact. Took four hours to find !
Good luck ! Oh ... No BBQ GN !


BBCTURBO11

agree^
sounds like the crank signal is being lost intermittently ,also check the crank sensor wires for damage where they are secured at the clamp at the fuel pump block off plate
a loose balancer bolt can do the same thing allowing the balancer to move forward and out of the sensor
and it could be the wires for the sensor at the ignition module have a break inside the the cam sensor could also be an issue

i also wouldnt be doing anything without a fresh fuel pump in the tank

 

[psycho6cyl]

x2 on crank wires. ran same way. left me stranded then ran fine stuck again over and over again. crank wires were bare and grounding out...

 

[BuickMike]

I also vote on crank sensor or wires to it. Way too many people keep blaming the coils, ign module, or MAF.

 

[earlbrown]

Sounds like a flakey cam sensor or compromised crank sensor wire (or an intermittent head related/bad ground on the ign module)


Physically inspect the crank sensor bracket, gap and wire running up the engine. When you fire it up, if it's acting right unplug the cam sensor and drive the car. If you can't get it to act up, it's probably the cam sensor. Don't forget during that test, if you turn the car off it won't start up without the signal.

 

[Powertechn2]

Thank you all for the advise. I appreciate it greatly.

I dug in today for a little bit. The plugs hadn't been changed in about 10 years. Oddly enough they looked amazingly fine, changed them anyways.

started looking at all the connectors. The cam sensor connector the rubber seal was smooshed and the connector was not all the way in. Not sure if that was the issue.

Found the crank sensor wires are all poofed up from being soaked in oil. Might remove the bad section and solder in new wires.

The owner of the car previous came by and we had a chat, him and I are good friends. He said the wires for the crank sensor were like that and he looked at them before and questioned them, but nothing was bare.

He also let me in on why he parked the car... THIS SAME ISSUE. So the issue started about 10 years ago. He said he tried everything and could never find the issue and got sick of messing with it and that is ultimately why he left the car parked on the lawn.

I did find an odd ground wire that comes thru the heater box to the ignition module bracket. It was just shoved onto the top of the stud. Not sure where this runs to. It is a small braided ground cable. Have to look into it.

I do have a better condition harness but don't want to swap it till the oil leaks are all fixed which likely won't happen till I build the girdled 109 block that I have.

As for the build I guess I should add it to my sig.

The maf is swapped to a 3 wire sensor. There is a translator.
I pulled off the air filter and noticed it appears there is a sensor that is threaded into the a/f base. Not sure why, this connector runs to the translator box. I am unsure what translator it is as the sticker is worn off. I know there are dip switches in the box.


From reading about the cam sensor I assume the ecu only NEEDS a signal to start up, then will run without it and just assume nothing is wrong?

I do have a scanmaster, just it was dark and I was not sure wth it was telling me. I started to cycle through the screens and found some odd readings that I don't remember ever seeing before. Did not record them as I was driving. Should have taken a video of what it was showing as I scrolled thru I guess.

As for the fuel pump, it is still making pressure. I have a long reach matco gauge I will just attach and tape to the windshield next time I drive the car and see if anything goofy is going on.

 

[pacecarta]

it will run after start without a cam signal but it wont be sequential , you will need to reconnect it to start the car . once the signal is lost it goes batch fire and you can test this by starting car and then unplug cam sensor and then drive and see if condition repeats .

the braided wire from heater box is a static drain for the heater core and should run to the firewall and secure with a screw

 

[Raeban]

I did find an odd ground wire that comes thru the heater box to the ignition module bracket. It was just shoved onto the top of the stud. Not sure where this runs to. It is a small braided ground cable. Have to look into it.

There is supposed to be a braided ground wire from the heater core that attaches to the firewall.

 

[Powertechn2]

Ok, so today had a chance to finish replacing the coil and module and the #6 plug. I knew ahead of time these were not the issue, at least it didn't seem like it.

Started the car, it ran good, then started running poorly, this time the cel came on, tried looking at codes thru the scanmaster, but while pushing buttons the car stalled... Restarted and then it ran fine and the cel was off.

Not really sure how to pull codes thru the scanmaster.

I think the crank sensor is likely the issue. It is oily as hell. I started to think of how the car likely operates. It probably used the crank sensor to tell it when to fire the injectors I would assume.
Also I found some more mystery connectors that go to nowhere, and one that goes to an old vacuum module of some sort.
Have to send pics from phone to puter then will post. It is late, haven't had dinner, long day at work, then at the car's garage.

 

[BuickMike]

The crank sensor tells the car when #1 is at TDC. The cam sensor tells the car when it is on the compression stroke. Clean the harness and check wires to the crank sensor. Make sure the bracket is tight. Make sure the balancer is not walking. Check the crank sensor to make sure it is lined up right and that it has not been hitting the balancer. I used to use the trick of using a piece cut out of a spray paint can lid to make sure the gap was correct. You can also get a flashlight and eyeball it to make sure it is centered.

 

[Nascar83Fan]

Any codes that are showing up will be under nal on scanmaster, with key on you can hit the left button on it and cycle through different things until you see nal with 2 digits to the right of it.
If no error codes are stored, it'll show 00.



Posted from the TurboBuick.Com mobile app

 

[Powertechn2]

Does the scanmaster store codes? I thought on older diagnostic systems the ecu would only show the code while the condition is there. Last 80's car I had was an 83 El Camino and the ecu was bypassed. It either ran or it didn't, was much more simplistic, then again, that was over 16 years ago.

I do remember seeing NAL then some numbers, but wasn't sure what I was looking at to be honest, and it was dark and I was trying to limp it home. I am used to 4 digit codes, and was trying to figure out what nal meant.

I tried to look closer at the crank sensor and the damned thing is soo oily that I couldn't tell what was what. I will get under there with some cleaner and spray it off, see if I can see what is what then. The crank pulley seems tight, at least I couldn't walk it back and forth by hand while squeezed under the car. I could see the ring which I think it gets it's signal from and it was clean and didn't show any signs of rubbing. It looked like there were two different adjustments for the sensor, one looked like you could adjust the time and the other looked like you could adjust the gap. Not 100% sure as it was all covered in oil. I guess the timing cover and the valve covers have really taken to leaking after it sat for so long.



Those are two of the mystery connectors. The rest I have figured out mostly. A few look like they went to the factory hydroboost brake system, one I think is the tach input, it's melted to shit, and not really sure where it would have gone originally.

I really appreciate the help btw.

I did have the manual for the scanmaster dl'd on my my computer, till the house got struck by lightning and it fried in june. Lost a ton of info, all the favorites for car info and parts.

I do plan on replacing the injectors and chip with one that plays better with the 10% ethanol, just I want to figure out this issue first.

Like I have said previously, I have a girdled 109 block and a lot better shape harness, just would much rather get the car running right as it sits before I go building an engine only to find the gremlins creeping up later.

 

[Raeban]

One of the connectors you are holding up is the factory wastegate solenoid and the other appears to be what is left of the factory oil pressure switch connector.

 

[Powertechn2]

Thanks. I kinda assumed the one with the vac ports was the factory waste gate, but was unsure of the others which are sticky dumdum'd together. I guess if it is just oil pressure switch then nothing could be shorting at least.

The guy that had done the resto on the car years ago was young, and I can only assume that he just figured that most of the bs wasn't necessary and instead of clipping and sealing the wires he just unplugged and called it a day.

I did laugh when he said he had the backfire issue and got sick of messing with it.

 

[BuickMike]

Somehow I think I remember that I had a friend that had an oil leak that would jack up how the car ran when it got into the crank sensor. Just go buy another one from the parts store, spray it all down to clean the oil, put it in, and see what happens.