Fault code H61
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,948
Likes: 2
From: Southern England
Fault code H61
Just taken the faults code of my 91 trying to sort the stuttering problem out on full power,ive looked through the manual but cant find the fault codes decoder(cant see the woods for the trees)
Ive got a couple of codes coming up which are C12 and H61.
Any ideas,thanks.
Ive got a couple of codes coming up which are C12 and H61.
Any ideas,thanks.
Melting Slicks
Joined: Dec 2004
Posts: 3,285
Likes: 52
From: Jacksonville, FL
St. Jude Donor '08 thru '26
Hi Cliff, "H" I think means "history" or a past code, usually found by asking the CCM. H61 in my 90 Helm manual is a secondary vacuum solenoid code. How did you come to get that "61" displayed? I don't have my helm or my book from Gordon K handy. I know the 61 on a 90 is sec. solenoid. The 12 if it flashes three times and then a pause and if there are any current codes they should be displayed and then the 12 flashes three times to signify the end of the test loop.
If 12 x 3 then nothing then 12 x 3 again there are no codes to show from the ECM that are current trouble in the system.
A scan tool usually will show "H" (history) codes or Gordon has a jumper to ask the CCM for history, trouble codes that are not currently causing a problem but were never cleared after the work was done. I think that is how it is supposed to work but I'm not too sure.
Don't know if this helps.
Tom
If 12 x 3 then nothing then 12 x 3 again there are no codes to show from the ECM that are current trouble in the system.
A scan tool usually will show "H" (history) codes or Gordon has a jumper to ask the CCM for history, trouble codes that are not currently causing a problem but were never cleared after the work was done. I think that is how it is supposed to work but I'm not too sure.
Don't know if this helps.
Tom
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,948
Likes: 2
From: Southern England
Originally Posted by tomtom72
Hi Cliff, "H" I think means "history" or a past code, usually found by asking the CCM. H61 in my 90 Helm manual is a secondary vacuum solenoid code. How did you come to get that "61" displayed? I don't have my helm or my book from Gordon K handy. I know the 61 on a 90 is sec. solenoid. The 12 if it flashes three times and then a pause and if there are any current codes they should be displayed and then the 12 flashes three times to signify the end of the test loop.
If 12 x 3 then nothing then 12 x 3 again there are no codes to show from the ECM that are current trouble in the system.
A scan tool usually will show "H" (history) codes or Gordon has a jumper to ask the CCM for history, trouble codes that are not currently causing a problem but were never cleared after the work was done. I think that is how it is supposed to work but I'm not too sure.
Don't know if this helps.
Tom
If 12 x 3 then nothing then 12 x 3 again there are no codes to show from the ECM that are current trouble in the system.
A scan tool usually will show "H" (history) codes or Gordon has a jumper to ask the CCM for history, trouble codes that are not currently causing a problem but were never cleared after the work was done. I think that is how it is supposed to work but I'm not too sure.
Don't know if this helps.
Tom
A friend and i put a paper clip in the plug and brought up the code,talk about frustrating ,today whilst driving on Normal power i came across ,or rather an Aston Martin Vantage came across me ,i had to act like i was just out cruising and as he headed out on the highway i had to decline running with him incase the hessitation cut in.
Time to get under that plenum.
Melting Slicks
Joined: Dec 2004
Posts: 3,285
Likes: 52
From: Jacksonville, FL
St. Jude Donor '08 thru '26
Cliff, put a vacuum pump on the line going under the plenum and see if the system holds vacuum. There is a vacuum line that goes from where the actuators are feed from, over to a MAP sensor under the ECM, on a 90 that is. That is how the ECM knows if the system holds the proper amount of vacuum. I think the ECM looks for 21kPa if the sys is working correctly. I would think that if the second MAP is N/G you could get a code 61 also. Either way there is a loss of vacuum from some place.
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,948
Likes: 2
From: Southern England
Tom,Would code 61 also apply to the injectors,do they have codes or is there an easier way of checking each injector.
When i put the key in and turned but didnt start the engine the vacum motor made the noise for a few seconds....i left the key on and the vacum motor didnt make the noise again..which tells me there is no leak,but is this only up to the secondary solenoid until you hit the secondaries?
I will whip the plenum off tomorrow and have a look,change the solenoid and actuators to see if this makes a difference.
Just to refresh the symptoms;
I step on it and as it accelerates on "Full" power it misses and stumbles and jerks.....this does not happen on "Normal" power.
When i put the key in and turned but didnt start the engine the vacum motor made the noise for a few seconds....i left the key on and the vacum motor didnt make the noise again..which tells me there is no leak,but is this only up to the secondary solenoid until you hit the secondaries?
I will whip the plenum off tomorrow and have a look,change the solenoid and actuators to see if this makes a difference.
Just to refresh the symptoms;
I step on it and as it accelerates on "Full" power it misses and stumbles and jerks.....this does not happen on "Normal" power.
Melting Slicks
Joined: Dec 2004
Posts: 3,285
Likes: 52
From: Jacksonville, FL
St. Jude Donor '08 thru '26
Code 61 & sec injectors
Cliff, There is no code that I'm aware of for the injectors. They're controlled but not directly monitered by the ECM. The feed back for injector function comes from the O2 sensors when the motor reaches "closed Loop" operation. The control is the pulse adjustment vs load(?) done by the ECM using the amount of O2 in the exhaust gas. So it is a feed back control loop, I believe, to get the A/F ratio correct??
Anyway, if the vacuum leak was big enough then the stumble would be right. Funny my solenoid was bad but no stumble. You say the pump shuts off after charging the system so everything up to & including the solenoid has to be good. Then the leak is after the solenoid, the actuators or the MAP on the ECM...I guess!!!! I'm not sure if I'm reasoning correctly. If the 2* ports don't open the car should go rich cause the 2* injectors should fire(??) and drown the motor with fuel(?) which would make for the stumble(?).
I think I don't know enough to be of much use on this. Maybe one of the other senior guys will see this & help you out.[ & me for that matter, maybe I'll learn something!]
Sorry Cliff.
Tom
Anyway, if the vacuum leak was big enough then the stumble would be right. Funny my solenoid was bad but no stumble. You say the pump shuts off after charging the system so everything up to & including the solenoid has to be good. Then the leak is after the solenoid, the actuators or the MAP on the ECM...I guess!!!! I'm not sure if I'm reasoning correctly. If the 2* ports don't open the car should go rich cause the 2* injectors should fire(??) and drown the motor with fuel(?) which would make for the stumble(?).
I think I don't know enough to be of much use on this. Maybe one of the other senior guys will see this & help you out.[ & me for that matter, maybe I'll learn something!]
Sorry Cliff.
Tom
Race Director
Joined: May 2000
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From: No more yankee my wankee, the Donger is tired!
Cliff is the stumble still present with a part throttle tip in?
Vacuum will be present for the secondaries under normal engine operation, unless something is wrong with the resevoir or the check valve.
Vacuum will be present for the secondaries under normal engine operation, unless something is wrong with the resevoir or the check valve.
Pro
Joined: Sep 2004
Posts: 656
Likes: 1
From: Nixa Mo.
Sounds like bad actuator. Mine held vacuum just fine but would not run hard with key on it would run up to about 5000 rpm and run out of steam. good luck. By the way if you order new actuator get two because more than likley one wont open properly. 
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Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,948
Likes: 2
From: Southern England
Originally Posted by tomtom72
Cliff, There is no code that I'm aware of for the injectors. They're controlled but not directly monitered by the ECM. The feed back for injector function comes from the O2 sensors when the motor reaches "closed Loop" operation. The control is the pulse adjustment vs load(?) done by the ECM using the amount of O2 in the exhaust gas. So it is a feed back control loop, I believe, to get the A/F ratio correct??
Anyway, if the vacuum leak was big enough then the stumble would be right. Funny my solenoid was bad but no stumble. You say the pump shuts off after charging the system so everything up to & including the solenoid has to be good. Then the leak is after the solenoid, the actuators or the MAP on the ECM...I guess!!!! I'm not sure if I'm reasoning correctly. If the 2* ports don't open the car should go rich cause the 2* injectors should fire(??) and drown the motor with fuel(?) which would make for the stumble(?).
I think I don't know enough to be of much use on this. Maybe one of the other senior guys will see this & help you out.[ & me for that matter, maybe I'll learn something!]
Sorry Cliff.
Tom
Anyway, if the vacuum leak was big enough then the stumble would be right. Funny my solenoid was bad but no stumble. You say the pump shuts off after charging the system so everything up to & including the solenoid has to be good. Then the leak is after the solenoid, the actuators or the MAP on the ECM...I guess!!!! I'm not sure if I'm reasoning correctly. If the 2* ports don't open the car should go rich cause the 2* injectors should fire(??) and drown the motor with fuel(?) which would make for the stumble(?).
I think I don't know enough to be of much use on this. Maybe one of the other senior guys will see this & help you out.[ & me for that matter, maybe I'll learn something!]
Sorry Cliff.
Tom
Hey no problem Tom dont worry about sorry this is a learning curve for us both and any other ZR-1 apprentices like us that are on the case,youve been a great help running through it with me,,i think what i will do tomorrow is sneak up on the sob with a bloody great hammer and scare it half to death
.Ive got all the secondary parts i took off my black 90 sitting in the loft so i will swap a few parts over and see what gives,the good thing is ive got the original actuators aswell,they work 100 percent.
It will be tally ho and off with its plenum tomorrow.
Thanks
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,948
Likes: 2
From: Southern England
Originally Posted by Jeffvette
Cliff is the stumble still present with a part throttle tip in?
Vacuum will be present for the secondaries under normal engine operation, unless something is wrong with the resevoir or the check valve.
Vacuum will be present for the secondaries under normal engine operation, unless something is wrong with the resevoir or the check valve.
Ive had a few pointers on the vacum system and the injectors so i will start by checking the vacum system first,what is a "Check Valve"?
Do the 90 & 91 vacum parts interchange?
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,948
Likes: 2
From: Southern England
Originally Posted by zesstey1
Sounds like bad actuator. Mine held vacuum just fine but would not run hard with key on it would run up to about 5000 rpm and run out of steam. good luck. By the way if you order new actuator get two because more than likley one wont open properly.
Melting Slicks
Joined: Dec 2004
Posts: 3,285
Likes: 52
From: Jacksonville, FL
St. Jude Donor '08 thru '26
Check valve
Cliff, the check valve is in the sec vac hose assembly on the line coming from the vac pump. After the connection point outside the plenum near the oil filter, the rest of the line goes under the plenum. The check valve is along that part of the line about 16" in from the outside connection, ya can't see it unless ya pull the plenum.
Tom
"becareful what you shoot at in here...somethings don't react well to bullits."
Tom
"becareful what you shoot at in here...somethings don't react well to bullits."
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,948
Likes: 2
From: Southern England
Originally Posted by tomtom72
Cliff, the check valve is in the sec vac hose assembly on the line coming from the vac pump. After the connection point outside the plenum near the oil filter, the rest of the line goes under the plenum. The check valve is along that part of the line about 16" in from the outside connection, ya can't see it unless ya pull the plenum.
Tom
"becareful what you shoot at in here...somethings don't react well to bullits."
Tom
"becareful what you shoot at in here...somethings don't react well to bullits."
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,948
Likes: 2
From: Southern England
Well i pulled the plenum off ,then myself and a couple of friends checked the vacum system,,every thing seems to work 100% although i will have another check tomorrow.
Its a bit dirty under there so i will have a clean up tomorrow and check the joins
Could this be the problem?,the hose has gone baggy and has not been holding a seal so ive taken it off and fitted a new one,what do you think.
Its a bit dirty under there so i will have a clean up tomorrow and check the joins
Could this be the problem?,the hose has gone baggy and has not been holding a seal so ive taken it off and fitted a new one,what do you think.
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,948
Likes: 2
From: Southern England
Originally Posted by zesstey1
Slow leak in actuator will cause code 61 put vac pump on one pump up to 12 and watch for slow leak. Slow leak will hold vac all over the place at the pump ect. check actuator by its self.
With the key turned "ON" but without engine running we unpluggedthe long hose running from the pump at the area by the alt...then unplugged a hose so we could plug the long pump hose straight to the actuators.....the actuators worked and we left them on there for a time but heard no pump noise..so we gathered that they were OK
We did the same with the reservoir ,the only thing i didnt check was the solenoid,,ime not sure how to check that one?
Do you think the way we did the check was a safe way or will i be better checking with a slow leak procedure?