96 vs 98 PCM car wont start!

Subject: 96 vs 98 PCM car wont start! Sun Sep 27, 2009 8:40 pm

I put in the 98 pcm into my riv to test it for the trans swap I have coming up.

I put in the 98, and the car wouldn't start. Put in 96 back in and it still wont start!

My mechanic thinks its an issue with the security VAT system. I bypassed security in my powertuner (I think) and the car still wont start up. Its getting fuel and spark. The plugs were dry so our theory of flooding the motor is out the door too.

It did something similar after the new injectors, but I checked the tune and the setting for my 42lb injectors are still in the bin.

what am I missing? why wont she start up?

no DTC's

_________________
'96 Riviera - 4T60E - DHP tuned
Exhaust: SLP headers, cat/EGR delete
Intake: CAI, 2.76" MPS, N*, ported sc, 42.5lb w/ PRJ fuel rails, S2 IC, Meziere IC pump, machined LIM, frozenboost IC radiator
Drivetrain: 1.9 roller rockers/pushrods, 105 valvesprings, AC delete
next: 2003 4T80E with 50K to go in

Subject: Re: 96 vs 98 PCM car wont start! Sun Sep 27, 2009 8:48 pm

dreww wrote:

Its getting fuel and spark.

If it's getting fuel and spark, it should run!

As I understand things, the '96 PCM and '98 PCM are not interchangeable without some rewiring. Hopefully you haven't damaged anything.

Try the 'brake cleaner trick' - take the vacuum line off from under the supercharger snout, hook a hose up to it and spray brake cleaner into the hose. Modulating the spray, you should be able to keep it running. If you can get it to run like this, your spark is okay and fuel is your problem. You should be able to keep it running like this for a while, I think I ran my car for 30 seconds or so like this.

IIRC if the VATS is pissed off, your fuel pump won't run. You can 'jump' the fuel pump by removing the relay and using a jumper wire across the appropriate terminals under the back seat.

_________________
'98 Buick Riviera; Gen V 3.25 pulley, N*, VS Cam, 180 stat, Custom PCM (Powrtuner), headers & HF cat , 42.5 lb inj.

Grant-built/PRJ/Thrasher trans 3.29 gears, 7/8 chain, zzp hardened IS

Subject: Re: 96 vs 98 PCM car wont start! Sun Sep 27, 2009 8:59 pm

Its not the fuel pump, you can hear it running. Im not real familiar with how the security system works.....could it be a VATS problem in your opinion?

and we checked the fuses, all of them (engine bay, panel and under rear seats)

_________________
'96 Riviera - 4T60E - DHP tuned
Exhaust: SLP headers, cat/EGR delete
Intake: CAI, 2.76" MPS, N*, ported sc, 42.5lb w/ PRJ fuel rails, S2 IC, Meziere IC pump, machined LIM, frozenboost IC radiator
Drivetrain: 1.9 roller rockers/pushrods, 105 valvesprings, AC delete
next: 2003 4T80E with 50K to go in

Subject: Re: 96 vs 98 PCM car wont start! Mon Sep 28, 2009 7:59 am

I think 98 you need to do a security learn. That is why I went with a 1997 PCM for my 4T65E conversion.

_________________

2001 Bonneville SSEI.
Engine: ZZP 3.2 MPS, Intense S1X Cam, PDM Ported SC, LS1 TB, PRJ wires, SS autochrome headers, ZZP UD WP, DHP Powertuner, 3.29 Gears, DIY Shift kit,
Handling: GXP STB, ES endlinks, DTS Front brakes, GXP Rear brakes.

Subject: Re: 96 vs 98 PCM car wont start! Mon Sep 28, 2009 9:18 am

oldsman105 wrote:

I think 98 you need to do a security learn. That is why I went with a 1997 PCM for my 4T65E conversion.

gotta get someone with a TechII to put the car's VIN into the 'new' PCM - after that then do a CASE learn.

Albertj

_________________
1998 with all fac. opts. (exc. CD changer and subwoofer); 209,000 miles. Mods: KYB front struts, extra noise barriers, fire extinguisher, Magnecor 8mm plug wires, 4-note horn, custom-made stainless exhaust.

Avatar is missing.

Subject: Re: 96 vs 98 PCM car wont start! Mon Sep 28, 2009 11:30 am

please tell me your shitting me?! Not only do I NOT know anyone with a tech II, Ive never even seen one or heard of someone who has one.

so basically Im fucked with this PCM? its worthless to me

and why wont it start with the 96 pcm anymore?

how do you do a CASE learn?

_________________
'96 Riviera - 4T60E - DHP tuned
Exhaust: SLP headers, cat/EGR delete
Intake: CAI, 2.76" MPS, N*, ported sc, 42.5lb w/ PRJ fuel rails, S2 IC, Meziere IC pump, machined LIM, frozenboost IC radiator
Drivetrain: 1.9 roller rockers/pushrods, 105 valvesprings, AC delete
next: 2003 4T80E with 50K to go in

Subject: Re: 96 vs 98 PCM car wont start! Mon Sep 28, 2009 11:43 am

DHP should be able to re-write vins and do a case learn. Try re-writing the vin in your 98 pcm to match your car.

_________________
1996 Riviera, 89k miles
Show: Tint ,Sherwood dash kit , PAU 17s , Magnaflow tips
Go: 1.9s ,FWI , 99+, Stage 1 TB, Plog + DP , 3.4" , Ported Gen III , decent tune.
Handlng: STB , Ma822s. STS 22mm rear sway bar.
Up next : KYB GR-2s ,

Subject: Re: 96 vs 98 PCM car wont start! Mon Sep 28, 2009 11:43 am

dreww wrote:

please tell me your shitting me?! Not only do I NOT know anyone with a tech II, Ive never even seen one or heard of someone who has one.

so basically Im fucked with this PCM? its worthless to me

and why wont it start with the 96 pcm

anymore?

how do you do a CASE learn?

Every GM dealer has a Tech II

_________________
1.9RR's, SSAC, LQ4 maf and N*, Gen V-ported, L32 LIM ported and polished, L26 block, L67 heads, tune, E85, 65# injectors
Worthy quotes:

Rickw wrote:

What a dipshit, grow up.

deekster_caddy wrote:

LOL @ guessing Rick's age. Since we've gotten together a couple of times I won't guess wink

he'd probably hit me

Subject: Re: 96 vs 98 PCM car wont start! Mon Sep 28, 2009 11:43 am

DHP should be able to re-write vins and do a case learn. Try re-writing the vin in your 98 pcm to match your car.

_________________
1996 Riviera, 89k miles
Show: Tint ,Sherwood dash kit , PAU 17s , Magnaflow tips
Go: 1.9s ,FWI , 99+, Stage 1 TB, Plog + DP , 3.4" , Ported Gen III , decent tune.
Handlng: STB , Ma822s. STS 22mm rear sway bar.
Up next : KYB GR-2s ,

Subject: Re: 96 vs 98 PCM car wont start! Mon Sep 28, 2009 2:28 pm

TonySmooth89 wrote:

DHP should be able to re-write vins and do a case learn. Try re-writing the vin in your 98 pcm to match your car.

Tony is correct.

I am not certain what amount of yelling or swearing will replace the VIN rewrite, but a little investigation probably would. Most major independent repair shops have ways to do it using various scan tools, and as I mentioned above Tony is correct.

You may have to rewrite the VIN in the '96 PCM; if I remember right it's something to do with the attempted PCM replacement. In the meantime you may find the following tutorial helpful:

http://www.hotrodlane.cc/ONLINETECH/computerrelearn.pdf

Albertj

_________________
1998 with all fac. opts. (exc. CD changer and subwoofer); 209,000 miles. Mods: KYB front struts, extra noise barriers, fire extinguisher, Magnecor 8mm plug wires, 4-note horn, custom-made stainless exhaust.

Avatar is missing.

Subject: Re: 96 vs 98 PCM car wont start! Mon Sep 28, 2009 3:02 pm

Drew, have you asked these questions on the DHP forums?

_________________
'98 Buick Riviera; Gen V 3.25 pulley, N*, VS Cam, 180 stat, Custom PCM (Powrtuner), headers & HF cat , 42.5 lb inj.

Grant-built/PRJ/Thrasher trans 3.29 gears, 7/8 chain, zzp hardened IS

Subject: Re: 96 vs 98 PCM car wont start! Mon Sep 28, 2009 5:42 pm

dreww wrote:

please tell me your shitting me?! Not only do I NOT know anyone with a tech II, Ive never even seen one or heard of someone who has one.

so basically Im fucked with this PCM? its worthless to me

and why wont it start with the 96 pcm anymore?

how do you do a CASE learn?

You car is not starting with the 1996 PCM? You may have another problem on your hands. I think you should try to get your car running with the 96 PCM before you go back to the 98 PCM.

_________________

2001 Bonneville SSEI.
Engine: ZZP 3.2 MPS, Intense S1X Cam, PDM Ported SC, LS1 TB, PRJ wires, SS autochrome headers, ZZP UD WP, DHP Powertuner, 3.29 Gears, DIY Shift kit,
Handling: GXP STB, ES endlinks, DTS Front brakes, GXP Rear brakes.

Subject: Re: 96 vs 98 PCM car wont start! Tue Sep 29, 2009 9:52 am

Like mentioned the 96 and 98 are wired differently. It is possible you blew out a sensor.

When you turn the key the fuel pump primes and the injectors fire a priming mist into the cylinders. The starter engages and spark is thrown. If vats is happy the injectors fire and the car runs. If Vats is tripped then the car runs for 2-5 seconds and stalls.

The main reason Oldsman chose the 97 pcm was because it had the 4T65 trans, SC motor and the wiring pinouts were the same as 96. Pinouts changed with the pcm in 98. That would have meant a new wiring harness or a lot of pin moving.

_________________

97 Bonneville SSEi: .579" and .592" lift.

Subject: Re: 96 vs 98 PCM car wont start! Tue Sep 29, 2009 12:53 pm

BillBoost37 wrote:

Like mentioned the 96 and 98 are wired differently. It is possible you blew out a sensor.

When you turn the key the fuel pump primes and the injectors fire a priming mist into the cylinders. The starter engages and spark is thrown. If vats is happy the injectors fire and the car runs. If Vats is tripped then the car runs for 2-5 seconds and stalls.

The main reason Oldsman chose the 97 pcm was because it had the 4T65 trans, SC motor and the wiring pinouts were the same as 96. Pinouts changed with the pcm in 98. That would have meant a new wiring harness or a lot of pin moving.

I apologize - did not knwo about the pinout changes. This may be big part of the problem.

Albertj

_________________
1998 with all fac. opts. (exc. CD changer and subwoofer); 209,000 miles. Mods: KYB front struts, extra noise barriers, fire extinguisher, Magnecor 8mm plug wires, 4-note horn, custom-made stainless exhaust.

Avatar is missing.

Subject: Re: 96 vs 98 PCM car wont start! Tue Sep 29, 2009 11:56 pm

so....wish I had known that before I got that 98 bill.

So what sensor do you think it was? I did notice the pinouts seems different on the 98.

my friend says the injectors are not pulsing at startup.

guess i'll try the tech article link posted above

_________________
'96 Riviera - 4T60E - DHP tuned
Exhaust: SLP headers, cat/EGR delete
Intake: CAI, 2.76" MPS, N*, ported sc, 42.5lb w/ PRJ fuel rails, S2 IC, Meziere IC pump, machined LIM, frozenboost IC radiator
Drivetrain: 1.9 roller rockers/pushrods, 105 valvesprings, AC delete
next: 2003 4T80E with 50K to go in