Intermittent Code 61 Ideas - ZR-1 Net Registry Forums

GOLDCYLON · 04-12-2010

Hi there GC needs a little help. I getting an intermittent SES light that wont hard set but always leads back to a code 61 (Secondary port throttle system error). Would a bad or non working vacuum pump cause this issue? It happens the most of the time when the Cruise control is set and the car has to pickup speed in 6th gear. As the car has to accelerate the SES light will illuminate and when the car levels off in terrain the light goes away. Im reading the troubleshooting section of the FSM and it appears when the Vacuum secondary actuators lose pressure that the ECM commands the air pump to kick in to compensate.

From what im reading either one of these actuators are suspect, as is a check valve, Air pump, secondary port actuator and the tubing. Asking if anybody else outthere has seen this repeat symptom. Is there a check for just the vaccum pump. I dont know if it ever comes on as my fans race on almost immediately in my car due to the prom setting. Just looking for ideas and any been there's and done thats. out there Thanks Daryll

jonszr1 · 04-12-2010

darrell, 2 things have you tried having someone turn the ignition on but not to start with you out by the vac pump .if it working it should go on for a very short period and then shut off. and 2 you can override the prom setting by taking your valet key and turning it off. then go put it in cruize control on the freeway and see what happens that will narrow it down for you . oh yeah there is also a fuse for the vacpump on the inside of the drivers wheel well . ck the service manual just to be sure . the fuse was out on my 92 when i first got it .dont know why it blew but replaced it and never had another problem . hope this helps

jonszr1 · 04-12-2010

also the corvette action center has a really good and quick troubleshooting guide in the zr1 section

tomtom72 · 04-13-2010

Daryl, I know you don't want to hear this but an intermittent 61 usually is vacuum related....usually. Figure the control solenoid is an on - off switch, so electrically it has to set a hard code if that side of it fails. If the vacuum side has a soft failure, like crap in it, then the 61 becomes intermittent. Likewise if the pull off canisters have soft failure in the rubbers, then maybe an intermittent 61 happens. Oh, also the second MAP sensor under the ECM where the ECM monitors the level of vacuum during secondary operation...that could also be the source of a 61, or any of the vacuum hose connected to any of the stuff under the plenum for the secondary system....which then goes back to the pump & any issues it could have.

JMHO
Tom

GOLDCYLON · 04-13-2010

Tom there is a seconary MAP sensoner under the ECM? I had no idea I thought there was only one behind the plenum. Is that on the underside of the ECM bracket?

bdw18_123 · 04-13-2010

Quote:

Originally Posted by tomtom72

Daryl, I know you don't want to hear this but an intermittent 61 usually is vacuum related....usually. Figure the control solenoid is an on - off switch, so electrically it has to set a hard code if that side of it fails. If the vacuum side has a soft failure, like crap in it, then the 61 becomes intermittent. Likewise if the pull off canisters have soft failure in the rubbers, then maybe an intermittent 61 happens. Oh, also the second MAP sensor under the ECM where the ECM monitors the level of vacuum during secondary operation...that could also be the source of a 61, or any of the vacuum hose connected to any of the stuff under the plenum for the secondary system....which then goes back to the pump & any issues it could have.

JMHO
Tom

So that's what that is. I saw that under the ECM on my '90 ZR-1, looks the same as the primary MAP sensor (minus the silver bracket). Was wondering why there was a second one. Good info, thanks Tom!

Quote:

Originally Posted by GOLDCYLON

Tom there is a seconary MAP sensoner under the ECM? I had no idea I thought there was only one behind the plenum. Is that on the underside of the ECM bracket?

Here is a picture of the one on my Z:

GOLDCYLON · 04-14-2010

Quote:

Originally Posted by bdw18_123

So that's what that is. I saw that under the ECM on my '90 ZR-1, looks the same as the primary MAP sensor (minus the silver bracket). Was wondering why there was a second one. Good info, thanks Tom!

Here is a picture of the one on my Z:

Great pic. I remembered that when I replaced my ECM holder about 6 months ago. I had no idea where that line went too until I traced it down. However dood... where the hell is your brake fluid lol?

Dynomite · 05-09-2010

Quote:

Originally Posted by tomtom72

Daryl, I know you don't want to hear this but an intermittent 61 usually is vacuum related....usually. Figure the control solenoid is an on - off switch, so electrically it has to set a hard code if that side of it fails. If the vacuum side has a soft failure, like crap in it, then the 61 becomes intermittent. Likewise if the pull off canisters have soft failure in the rubbers, then maybe an intermittent 61 happens. Oh, also the second MAP sensor under the ECM where the ECM monitors the level of vacuum during secondary operation...that could also be the source of a 61, or any of the vacuum hose connected to any of the stuff under the plenum for the secondary system....which then goes back to the pump & any issues it could have.
JMHO
Tom

Quote:

Originally Posted by bdw18_123

So that's what that is. I saw that under the ECM on my '90 ZR-1, looks the same as the primary MAP sensor (minus the silver bracket). Was wondering why there was a second one. Good info, thanks Tom!

Here is a picture of the one on my Z:

Quote:

Originally Posted by FULLPWR

Hey John, I just replaced both on my 90 with ACDELCO's, under the ECM the acdelco box it came in states the same no. for ac/gm
ACD# 16232241
GM# 16232241

MAP SENSOR back of plenum
ACD# 213-1545
GM# 12569240

Luis

Just putting all this together

GOLDCYLON · 04-13-2010

Quote:

Originally Posted by Dynomite

I would much rather chase a vacuum connection/leak than an electrical connection/leak

Agreed

QB93Z · 04-13-2010

GC, I am not sure if the Code 61 is related but here is what I observed on a 1994.

There is a pressure switch that monitors Secondary Vacuum and turns OFF the Secondaries if they have been commanded ON and the Secondary Vacuum drops too low to hold the secondaries open.

During acceleration, the Secondary system would cycle on and off. I had a scanner connected to the car during operation. What was happening was that a bad check valve between the secondaries and the other vacuum uses allowed vacuum "loss" when manifold air pressure went up (throttle valves wide open). The secondary vacuum pressure switch would sense rising pressure (loss of vacuum) and would shut off the secondaries. I believe that a code occurs from that event.

Jim

04-12-2010	#1
GOLDCYLON Join Date: May 2007 Location: Peoria, AZ Posts: 9,155	Intermittent Code 61 Ideas Hi there GC needs a little help. I getting an intermittent SES light that wont hard set but always leads back to a code 61 (Secondary port throttle system error). Would a bad or non working vacuum pump cause this issue? It happens the most of the time when the Cruise control is set and the car has to pickup speed in 6th gear. As the car has to accelerate the SES light will illuminate and when the car levels off in terrain the light goes away. Im reading the troubleshooting section of the FSM and it appears when the Vacuum secondary actuators lose pressure that the ECM commands the air pump to kick in to compensate. From what im reading either one of these actuators are suspect, as is a check valve, Air pump, secondary port actuator and the tubing. Asking if anybody else outthere has seen this repeat symptom. Is there a check for just the vaccum pump. I dont know if it ever comes on as my fans race on almost immediately in my car due to the prom setting. Just looking for ideas and any been there's and done thats. out there Thanks Daryll __________________ GOLDCYLON - 91 ZR-1 #2014 GOLDCYLON - 90 ZR-1 #2794, 4L60e (Formerly Schrade's) GOLDCYLON - 11 CTS-V Arizona State Director 91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat 90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat 11 RED/GREY CTS-V Last edited by GOLDCYLON; 04-12-2010 at 05:12 PM.

04-12-2010	#2
jonszr1 Join Date: Sep 2006 Location: lone pine and mammoth lakes Posts: 1,407	Re: Intermittent Code 61 Ideas darrell, 2 things have you tried having someone turn the ignition on but not to start with you out by the vac pump .if it working it should go on for a very short period and then shut off. and 2 you can override the prom setting by taking your valet key and turning it off. then go put it in cruize control on the freeway and see what happens that will narrow it down for you . oh yeah there is also a fuse for the vacpump on the inside of the drivers wheel well . ck the service manual just to be sure . the fuse was out on my 92 when i first got it .dont know why it blew but replaced it and never had another problem . hope this helps

04-12-2010	#3
jonszr1 Join Date: Sep 2006 Location: lone pine and mammoth lakes Posts: 1,407	Re: Intermittent Code 61 Ideas also the corvette action center has a really good and quick troubleshooting guide in the zr1 section

04-13-2010	#4
tomtom72 Join Date: Dec 2004 Location: Jacksonville, FL USA Posts: 4,645	Re: Intermittent Code 61 Ideas Daryl, I know you don't want to hear this but an intermittent 61 usually is vacuum related....usually. Figure the control solenoid is an on - off switch, so electrically it has to set a hard code if that side of it fails. If the vacuum side has a soft failure, like crap in it, then the 61 becomes intermittent. Likewise if the pull off canisters have soft failure in the rubbers, then maybe an intermittent 61 happens. Oh, also the second MAP sensor under the ECM where the ECM monitors the level of vacuum during secondary operation...that could also be the source of a 61, or any of the vacuum hose connected to any of the stuff under the plenum for the secondary system....which then goes back to the pump & any issues it could have. JMHO Tom __________________ 1990 ZR-1, Black/grey, #2233, stock. ZR-1 Net Reg Founding Member #316 & NCM member

04-13-2010	#5
GOLDCYLON Join Date: May 2007 Location: Peoria, AZ Posts: 9,155	Re: Intermittent Code 61 Ideas Tom there is a seconary MAP sensoner under the ECM? I had no idea I thought there was only one behind the plenum. Is that on the underside of the ECM bracket? __________________ GOLDCYLON - 91 ZR-1 #2014 GOLDCYLON - 90 ZR-1 #2794, 4L60e (Formerly Schrade's) GOLDCYLON - 11 CTS-V Arizona State Director 91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat 90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat 11 RED/GREY CTS-V Last edited by GOLDCYLON; 04-13-2010 at 01:59 PM.

04-13-2010	#10
QB93Z Join Date: May 2007 Location: Westminster, Maryland Posts: 3,689	Re: Intermittent Code 61 Ideas GC, I am not sure if the Code 61 is related but here is what I observed on a 1994. There is a pressure switch that monitors Secondary Vacuum and turns OFF the Secondaries if they have been commanded ON and the Secondary Vacuum drops too low to hold the secondaries open. During acceleration, the Secondary system would cycle on and off. I had a scanner connected to the car during operation. What was happening was that a bad check valve between the secondaries and the other vacuum uses allowed vacuum "loss" when manifold air pressure went up (throttle valves wide open). The secondary vacuum pressure switch would sense rising pressure (loss of vacuum) and would shut off the secondaries. I believe that a code occurs from that event. Jim __________________ If it isn't fun, you aren't doing it right! 1990 Black ZR-1 - sold 1993 Quasar Blue ZR-1 1994 Competition Yellow ZR-1 1995 Dark Purple ZR-1 Maryland State Coordinator WAZOO Member