inconsistent surge. hard to pinpoint the problem.

ScottHeidinger

Active Member
May 2, 2015
680
116
43
50
northeast Florida
whenever this surge happens the car never dies completely, I take my foot off the gas and it cuts in and out for mabye 2 -3 secs, check engine light flashes on and off like mad. and sometimes even resets the computer whenever it happens. my scanmaster readings will flip out and give me a bunch of different error codes and then go back to 00 once its done having an aneurysm lol what is happening?!?!?!
Sounds like the ECM is intermittently loosing power.
I would follow the orange wire at the battery that provides power to the ECM. I had one end up melted on the passenger header and it would randomly blow the fuse. Maybe you have a bad connection somewhere in the ECM power orange wire that starts at the battery cable.


Sent from my iPhone using Tapatalk
 

TurboBuRick

Moderator
Staff member
Feb 18, 2006
9,150
445
83
47
South subs. of Chicago
Definitely computer or electrical connection related. Possible bad chip connection. Pull the chip and pry up leads with a safety pin.

Unplug the ecm and look for white corrosion in the sockets.

Make sure battery cables are tight. Make sure the orange wire connector is getting a good connection.

Trace the positive battery cable down to the starter. Make sure it’s not touching the header and burned through insulation. It can short out on the header.
 

Thomas Steven Booth

New Member
Apr 3, 2016
13
0
1
29
So I’ve gone around and done everything recommended by you guys, no luck :( I went ahead and bought some 60s w a turbo tweak chip, in case it was a bad injector, plus I didn’t know what kind of chip I had in the car so it didn’t hurt to install those. My Orange ECM wire was re-routed a while ago and runs up the fender and doesn’t touch the heads/manifold, neither do the alternator wires.. the fuse link for the ecm is fine, I replaced the old TPS and adjusted it properly along with the IAC. I’ve wiggled every wire/relay in the car and it doesn’t cut out. It only seems to cutout when it’s in gear. Also I replaced the ECM.. probably didn’t have to but I thought given the symptoms, I could’ve fried the computer... but that wasn’t the case. Oh well ‍♂

I’ve noticed while I’m driving and my lights are on, my stock rpm gauge (which doesn’t work) starts flickering at random times. Note: my dash lights don’t work, so whenever I turn my headlights on the rpm gauge light turns off. So, as I’m driving the rpm gauge will begin to flicker on rapidly, And once it stops flickering, my car bogs, the check engine light flashes on and off, and my scanmaster throws codes at me but the car never completely dies... so I can tell when it’s about to bog/misfire based on what that’s doing. Anything ideas based on that?

Btw I truly appreciate all the help and suggestions : ). this car has been in my family for years, my dad used to pick me up from elementary school in this thing and I also drove it throughout high school. it’s my favorite car of all time and I’m never selling it! So I’m determined to figure this out and learn more about this legend in the process. Thanks for the patience in advance. it can’t be anything major, it’s just impossible to pinpoint
 
Last edited:

dank GN

BlackArts Automotive (661)993-8277
Jan 11, 2009
3,595
431
83
SoCal the high desert
Have you checked your fuseable links ? They are all connected to your starter and are routed by your hot ass headers . They could be causing some weird issues definitely worth checking it out .
 

Chuck Leeper

8/10's of a century!
Staff member
May 28, 2001
11,930
1,560
113
Madison, Ga.
When the car was returned to the street, did you find any mouse/rat shit, anywhere?
Have you looked under the dash, inspected the wiring, cleaned the connections?
Have you pulled the main body plug at the fuse panel/firewall, and checked for corrosion, etc?

A clue?
"Note: my dash lights don’t work, so whenever I turn my headlights on the rpm gauge light turns off. So, as I’m driving the rpm gauge will begin to flicker on rapidly, And once it stops flickering, my car bogs, the check engine light flashes on and off."

A data log could/would help find this.
I'm suspecting a hi load short is pulling the voltage down so far, that the ign and injectors go bonkers. Thus the bog.
Take a look at the 2 connectors hanging behind the alternator. One is green, one is black. What do you see?
 

Thomas Steven Booth

New Member
Apr 3, 2016
13
0
1
29
which codes?
Different codes each time, my most recent I got 51, 53, 54. And once the car finished it’s bog it returned to 00. I also remember getting 41 and 35. At this point I think I’ve gotten almost half of the error codes pop up and disappear. And fuel pressure rises 1to1
 

Thomas Steven Booth

New Member
Apr 3, 2016
13
0
1
29
When the car was returned to the street, did you find any mouse/rat shit, anywhere?
Have you looked under the dash, inspected the wiring, cleaned the connections?
Have you pulled the main body plug at the fuse panel/firewall, and checked for corrosion, etc?
Haven’t done that yet, I checked my fuses a while back that’s really it. But the car hasn’t been sitting for long as of recently, it’s been my everyday driver for 4 years now, if any of the rat shit is still on the car id be surprised. I’ve cleaned it inside and out pretty thoroughly multiple times. I haven’t checked ALL the connections in the car, but I haven’t found any corrosion or rust in the ECM connections. I’ve gone ahead and looked at the diagram on gnttype.org and tried wiggling every relay trying to get the car to bog but alas, nothing. Only happens when I’m in gear driving around where body shake is at its max.
 

ttypewhite

Well-Known Member
Oct 1, 2001
3,180
496
83
46
Toronto
I'm willing to bet it is your grounds at the back of the head or intake. You have broken wire at one of those points that still makes contact, but not good enough under those conditions where you are having the problem. Check them out along with the ground coming off the battery to the bracket for the turbo shield on the block, and passenger side firewall for the negative terminal.
 

ScottHeidinger

Active Member
May 2, 2015
680
116
43
50
northeast Florida
The rat shit thing is more about the damage they may have done to the wiring in the car not so much the actual shit they left behind. If you had them in the car you should look for damage they may have done to the wiring and vacuum lines. The grounds listed in the above post should be checked first. It’s hard to see the ground that attaches to the back of the head and the one on turbo bracket.
Squirrels, rats and mice will all eat damn near anything. A friend has a truck that was running like shit and when he took it to the dealership because it was under warranty and only a year old they found squirrels had chewed up several vacuum lines. They fixed it and 2 months later it happened again. I have no idea why they liked to eat them but he had to get rid of the squirrels and the warranty didn’t cover rodent damage. I’ve seen issues with cars that sat in garages that rats ate the wiring under the dash so If you had rat shit it’s a good possibility they may have done some damage.



Sent from my iPhone using Tapatalk
 

captndave737

Active Member
Feb 14, 2006
994
170
43
66
Raleigh, NC
Different codes each time, my most recent I got 51, 53, 54. And once the car finished it’s bog it returned to 00. I also remember getting 41 and 35. At this point I think I’ve gotten almost half of the error codes pop up and disappear. And fuel pressure rises 1to1
CODE 51- MEM CALPAC error
53- ECM error
54- not listed in the shop manual
41-CAM SENSOR
35-Not listed
 

MikeS

Member
Oct 30, 2012
85
22
8
Check the grounds like t type white said. You can pick up sections of 6 gauge wire with terminals from Walmart or the auto parts store for a few bucks and add more to be sure you have proper grounding- battery to engine, engine to chassis, battery to body, etc...Those original ground wires are old now. Also re-check the PCM power wire. Mine broke inside the rubber coating right by the battery, resulting in some of what you're describing. I only found it by accident when I saw it arc. Good luck, electrical gremlins are a bitch.
 

NY Twin Turbo

All the good stuff.....Times 2.
Dec 10, 2014
2,605
942
113
47
Westchester NY
Haven’t done that yet, I checked my fuses a while back that’s really it. But the car hasn’t been sitting for long as of recently, it’s been my everyday driver for 4 years now, if any of the rat shit is still on the car id be surprised. I’ve cleaned it inside and out pretty thoroughly multiple times. I haven’t checked ALL the connections in the car, but I haven’t found any corrosion or rust in the ECM connections. I’ve gone ahead and looked at the diagram on gnttype.org and tried wiggling every relay trying to get the car to bog but alas, nothing. Only happens when I’m in gear driving around where body shake is at its max.
Your definitely loosing power to everything intermittently!

Especially your computer.

Maybe your battery has an internal short.

Shake it. See what happens.
 

Thomas Steven Booth

New Member
Apr 3, 2016
13
0
1
29
Well, after months of trying different things, installing a new coolant sensor seemed to do the trick. It makes absolutely no sense to me and it’s honestly the last thing I’d think of. It no longer has the check engine light misfire problem, scanmaster reads no malfunction codes which is satisfying, and it’s been running very nice with those 60 lb injectors + Turbo Tweak chip. I’ve been driving it to and from work for about 2 days now. However I started it up earlier, and as I was waiting for it to warm up and it sputtered and died right there in my driveway. Turned it over again and it died almost immediately. Then it wouldn’t turn over at all. I thought I ran out of gas or something. But I let it sit for mabye an hour and it turned over and idled like nothing happened... Odd... with the problem I was having before the car wouldn’t die, and now it is dying, with completely different symptoms. Sigh.
 

NY Twin Turbo

All the good stuff.....Times 2.
Dec 10, 2014
2,605
942
113
47
Westchester NY
Well, after months of trying different things, installing a new coolant sensor seemed to do the trick. It makes absolutely no sense to me and it’s honestly the last thing I’d think of. It no longer has the check engine light misfire problem, scanmaster reads no malfunction codes which is satisfying, and it’s been running very nice with those 60 lb injectors + Turbo Tweak chip. I’ve been driving it to and from work for about 2 days now. However I started it up earlier, and as I was waiting for it to warm up and it sputtered and died right there in my driveway. Turned it over again and it died almost immediately. Then it wouldn’t turn over at all. I thought I ran out of gas or something. But I let it sit for mabye an hour and it turned over and idled like nothing happened... Odd... with the problem I was having before the car wouldn’t die, and now it is dying, with completely different symptoms. Sigh.
Your problem wasn't the coolant sensor. And I think it just got worse.

I believe you are still loosing power to something intermittently, but maybe more frequently and for longer intervals. Maybe start thinking about it being an ignition module.

Either way, I wouldn't trust it outside of the pushing distance from your driveway.
 

Thomas Steven Booth

New Member
Apr 3, 2016
13
0
1
29
Your problem wasn't the coolant sensor. And I think it just got worse.

I believe you are still loosing power to something intermittently, but maybe more frequently and for longer intervals. Maybe start thinking about it being an ignition module.

Either way, I wouldn't trust it outside of the pushing distance from your driveway.
I replaced all my fuse links, and I’ve also replaced my ignition module 3 times already. Gone through with plugs and wires, coil pack, maf, new battery, and my alternator isn’t even 3 years old. It’s not cutting out rapidly anymore. I honestly didn’t think it was the coolant sensor either, but the car ran great for 2 days without a single hiccup. It only just started this last night, seems fine when the engine is cold, but as soon as it reached 170 it seemed to want to die on me, backfired a couple times while I was driving it, and then it died at a light trying to idle. But started back up and I barely got it home. I think it shut off 3 times in my neighborhood lol. Seems completely different from the problem I was having before when my check engine light was having an aneurism. Because my car never completely died before with that problem... It was always able to at least idle ok. Check engine light doesn’t even pop up anymore when it sputters and bogs with this new prob. This car is a goddamn mystery I swear
 

ScottHeidinger

Active Member
May 2, 2015
680
116
43
50
northeast Florida
Check your Hotwire connector at back of alternator. Mine looked fine but would randomly have fuel pressure issues that I could see on the fuel pressure gauge. Car ran fine but the connector had corrosion inside it under heat shrink tubing. Made a connection but wasn’t good enough to carry the current required at high boost. Fuel pressure gauge would bounce around. Replaced that connector and it stopped. I’m just thinking maybe you moved the wires around and it made a better connection for a while. Could also be 30 year old connections in wiring harness. Maybe not making good contact or corrosion.


Sent from my iPhone using Tapatalk
 
  • Like
Reactions: Thomas Steven Booth

NY Twin Turbo

All the good stuff.....Times 2.
Dec 10, 2014
2,605
942
113
47
Westchester NY
I replaced all my fuse links, and I’ve also replaced my ignition module 3 times already. Gone through with plugs and wires, coil pack, maf, new battery, and my alternator isn’t even 3 years old. It’s not cutting out rapidly anymore. I honestly didn’t think it was the coolant sensor either, but the car ran great for 2 days without a single hiccup. It only just started this last night, seems fine when the engine is cold, but as soon as it reached 170 it seemed to want to die on me, backfired a couple times while I was driving it, and then it died at a light trying to idle. But started back up and I barely got it home. I think it shut off 3 times in my neighborhood lol. Seems completely different from the problem I was having before when my check engine light was having an aneurism. Because my car never completely died before with that problem... It was always able to at least idle ok. Check engine light doesn’t even pop up anymore when it sputters and bogs with this new prob. This car is a goddamn mystery I swear
I'm sorry bro. I wish I could offer you more as far as where to look. But this seems to be one of those things that needs to be dug into deep. I would start by forgetting everything I know up until this point and starting over.

First thing I would do is dig in to the entire electrical system starting with wire schematics in hand, shaking the harness and doing a visual inspection and a multi-meter, test light and a jump-wire with alligator clips.. Jack the car way up, open the hood, doors, and trunk, remove all under dash panels, Especially the areas of the starter, all grounds, battery, fuse panel, bulkhead connections, ECM, ignition switch, everywhere, everyplace, and again. If this takes you less than a solid full 8 hour day, then you probably not deep enough into it.

Next, find a real good Buick friend who's car runs perfectly. Then focus on the hard parts. Every sensor or control device that can be checked electrically should be checked first. Then later can be swapped out for testing from your buddies car.

If none of this works, set it on fire.

Only kidding.

Also, just re-read your post above. Maybe your IAC is a freezing up. I only was led to this guess because you said "seems fine when the engine is cold, but as soon as it reached 170 it seemed to want to die on me". This once led to my discovery of a bad IAC once.

Then take it to a Buick shop.
 
  • Like
Reactions: Thomas Steven Booth
Top Bottom