HomeDashboardFAQSearchRiviera Questions & AnswersWrite-Ups IndexRegisterRelated LinksMemberlistLog in

Share | 
 

 Stalling after warming up

View previous topic View next topic Go down 
AuthorMessage
ajgee2011
Amateur
avatar

Name : A.J. Gee
Age : 23
Location : lovington, IL
Joined : 2011-12-10
Post Count : 40
Merit : 1

PostSubject: Stalling after warming up   Sun Oct 08, 2017 7:08 pm

Hello everyone,
So i have a 95 Riv with a series 1 supercharged. I had it in the shop about 6 months ago to have supercharger rebuilt and the harmonic balancer replaced. After that visit car ran great until a couple months later. Then i would start the car up fine maybe sometimes having a rough idle, but ran fine. After driving for 15 minutes the car would begin to misfire, it would do it until I would pull over and shut the car off. Then I would turn the car back on and it would run fine for the next 15 minutes. I took the car in the shop and they said it was the lower intake gasket or plenum gasket. I got that fixed and the problem was gone. Now a couple months later again the problem came all back again with it misfiring or stalling after about 15 minutes of driving.

Like i said the car sometimes also starts pretty rough and not idling correctly, and sometimes it will even turn on the check egine light but it goes right off after a restart.

Any help would be appreciated because I am starting to grow sceptical of the shop I am taking it to.
Back to top Go down
albertj
Guru
avatar

Name :
Location : Finger Lakes of New York State
Joined : 2007-05-31
Post Count : 6752
Merit : 124

PostSubject: Re: Stalling after warming up   Tue Oct 10, 2017 12:13 am

did the shop replace the lower intake gasket, or just re-torque.
Back to top Go down
ajgee2011
Amateur
avatar

Name : A.J. Gee
Age : 23
Location : lovington, IL
Joined : 2011-12-10
Post Count : 40
Merit : 1

PostSubject: Re: Stalling after warming up   Tue Oct 10, 2017 2:51 am

Replaced the gasket
Back to top Go down
Mr.Riviera
Expert
avatar

Name : Matthew
Age : 31
Location : Florida
Joined : 2007-01-17
Post Count : 4353
Merit : 99

PostSubject: Re: Stalling after warming up   Tue Oct 10, 2017 10:26 am

Could also be a coil pack starting to go or ICM connection is bad. They would have pulled this when doing LIM most likely. Wonder if you tap on them it will make the car idle worse/better. How old are the plugs/wires?

_________________
1996 with 244k miles, L32 4" FWI -> ported N* -> Ported Gen V w/3.0" Pulley, Stage 3 Phenolic I/C, ZZP FMHE, 1.84 RR, Headers and 3" pipe to mufflers, F-body brakes, and lowered on Eibachs.
Back to top Go down
ajgee2011
Amateur
avatar

Name : A.J. Gee
Age : 23
Location : lovington, IL
Joined : 2011-12-10
Post Count : 40
Merit : 1

PostSubject: Re: Stalling after warming up   Tue Oct 10, 2017 12:01 pm

Cannot say for sure how old the plugs and wires are, i have had the car about a year. I did check them and they seem alright.
Back to top Go down
albertj
Guru
avatar

Name :
Location : Finger Lakes of New York State
Joined : 2007-05-31
Post Count : 6752
Merit : 124

PostSubject: Re: Stalling after warming up   Tue Oct 10, 2017 12:41 pm

did you test the coils with your VOM yet? If so, do they match? (this is important)
Back to top Go down
ajgee2011
Amateur
avatar

Name : A.J. Gee
Age : 23
Location : lovington, IL
Joined : 2011-12-10
Post Count : 40
Merit : 1

PostSubject: Re: Stalling after warming up   Tue Oct 10, 2017 1:28 pm

I pulled the plugs off each coil pack one by one are seem to be firing alright, one was a little wonky so i swapped it and and didnt help. Do not have anything to fully test coils.
Back to top Go down
albertj
Guru
avatar

Name :
Location : Finger Lakes of New York State
Joined : 2007-05-31
Post Count : 6752
Merit : 124

PostSubject: Re: Stalling after warming up   Tue Oct 10, 2017 5:14 pm

ajgee2011 wrote:
I pulled the plugs off each coil pack one by one are seem to be firing alright, one was a little wonky so i swapped it and and didnt help. Do not have anything to fully test coils.



To test the coils, just pull them one by one (car off of course) and measure:

  1. resistance across primary

  2. resistance across secondary

  3. if there is any conductivity between primary and secondary


That fully tests the coils.  Any conductivity from primary to secondary and you have a bum coil.  Any coil that is far off in values from the others is a problem too; more on that below.  

Here's your headache: (parts of the following are from http://www.underhoodservice.com/servicing-gm-s-3800-v6-engines/2/)

On this engine, as you know/can see by how it's set up, each coil fires two cylinders at a time; on each firing, one spark plug fires with normal polarity while its companion plug fires with reverse polarity. (by the way this is one of the reasons for all the other electrical fun we have with these cars -- they have what some call a "floating ground.") Because the ignition coil requires approximately 30% more voltage to fire a spark plug with reverse polarity, the ignition coil requires more saturation time (longer dwell) and a higher primary current. This allows the coils to produce up to 40Kv if needed.  AFAIK it's one of the highest energy ignition systems out there *in stock trim* on the SC engine.

The headaches:  the coils for the NA and SC engines are physically interchangeable but electrically different.  If you test a coil with an ohmmeter, the test specs are 0.5 to 0.9 ohms for the primary terminals under the coil, and secondary resistance of 5,000 to 8,000 ohms at the high-voltage terminal. The SC (supercharged) coils have lower primaries, and higher secondaries, if I remember right, given those ranges.  Point is, if you measure the coils and the values do not match *coil to coil,* that mismatch (plus marginal wires in most cases) will lead to misfiring.  What happens is for one reason or another people get the wrong coils on.  Typically this is when someone with the SC engine gets a coil from a parts store and ends up with a NA coil.  They are sold as interchangeable but that's just wrong -- they will work but they won't work well and fail fast leading to other problems.   Also, because the energy is so high in the first place, worn wires can cause all kinds of problems. More on that later.  Finally, the coils run hot.  If you don't have enough non-conductive tune up grease on the ignition coil ground plate, then the ignition coils will overheat (which maybe might be why your car runs poopy when warm).

If your coils don't match, go to a junkyard and find another car with the 3800 engine same as yours (NA or SC) and buy the coil set.   Measure those with a meter - either at the yard before you buy or at home.  Use the three that match up primary-to-primary and secondary to secondary best, provided they don't leak from primary to secondary. As for wires, you might need to get a set of Delco factory wires.  The energy from this system is really high and it pops or fries  lesser wires quickly over time. The Delco wires don't cost that much even at a GM dealer... but you might try a Delco parts dealer in your town or one of the online merchants via eBay or Amazon.

Finally you need to recheck the wires going into the ignition control module (the coil pack base).  There was a problem with those wires work hardening and breaking inside the insulation, on some of the mid-90s cars.  You will have to check them carefully. Very carefully.

Let us know what you find, we'll continue from there.

Albertj
Back to top Go down
ajgee2011
Amateur
avatar

Name : A.J. Gee
Age : 23
Location : lovington, IL
Joined : 2011-12-10
Post Count : 40
Merit : 1

PostSubject: Re: Stalling after warming up   Sat Oct 14, 2017 12:16 am

So i decided to take my care into a different shop. Things were just going a little beyond my knowledge. After 3 days they got back to me and said for starters the intake gasket I just had replaced was leaking along with the thermostat housing. They also said they cannot pin point the exact reason the car is stalling/misfiring yet, but are pretty sure it is an electrical issue, which i was komd of figuring. So hopefully will hear back soon.
Back to top Go down
ajgee2011
Amateur
avatar

Name : A.J. Gee
Age : 23
Location : lovington, IL
Joined : 2011-12-10
Post Count : 40
Merit : 1

PostSubject: Re: Stalling after warming up   Sat Oct 14, 2017 12:17 am

I am a body, and stereo guy, I know a good bit about engine work but this was going beyond what I know.
Back to top Go down
albertj
Guru
avatar

Name :
Location : Finger Lakes of New York State
Joined : 2007-05-31
Post Count : 6752
Merit : 124

PostSubject: Re: Stalling after warming up   Sat Oct 14, 2017 2:07 pm

ajgee2011 wrote:
So i decided to take my care into a different shop. Things were just going a little beyond my knowledge. After 3 days they got back to me and said for starters the intake gasket I just had replaced was leaking along with the thermostat housing. They also said they cannot pin point the exact reason the car is stalling/misfiring yet, but are pretty sure it is an electrical issue, which i was komd of figuring. So hopefully will hear back soon.

you could share these posts with the shop....
Back to top Go down
ajgee2011
Amateur
avatar

Name : A.J. Gee
Age : 23
Location : lovington, IL
Joined : 2011-12-10
Post Count : 40
Merit : 1

PostSubject: Re: Stalling after warming up   Sat Oct 14, 2017 7:38 pm

Will do, will let you know what i find out.
Back to top Go down
Sponsored content




PostSubject: Re: Stalling after warming up   

Back to top Go down
 
Stalling after warming up
View previous topic View next topic Back to top 
Page 1 of 1
 Similar topics
-
» Stalls at traffic lights...
» My engine keeps stalling out?
» Stalling after fill-up
» Stalling/running rough
» '95 SC Riviera Intermittent Stalling & Flashing PRND321

Permissions in this forum:You cannot reply to topics in this forum
Riviera Performance ::   Supercharged 3800 Tech :: Series I Engine & Transmission-
Jump to: