Secondary Vacuum Solenoid

[jeasen]

First I want to introduce myself, I use the screen name of Jeasen and I am new to this board. I am also a new ZR1 owner (1990 Red on Red). Although I have owned, maintained and drag raced Buick Grand Nationals for years this is my first ZR1.

I want to thank all the ZR1 guys that have gone before me and say Thank You for all the information available on the ZR1. The information is very valuable to a new owner. I was able to diagnose and repair my fuel pump problem for the cost of a couple of metal clamps. Thanks again for the help available in the How To section.

I am now trying to fix my Vacuum Problem and get the secondaries working. I started diagnosing the problem last night using information available on this board. It was not long and I found that the plenum needed to be removed. Once the plenum was removed I started checking the vacuum lines in different places. The plastic vacuum lines and the rubber connectors were all good. The actuators are both good (I was using a vacuum pump). The problem is the Vacuum Solenoid (Part #1999222).

Now my problem, I called the Chevy Dealer and the part is no longer available. I would like to know if one of you guys know of a replacement part that would work??? If not can I just remove this part and jumper the vacuum lines??? What has been you experience?? I feel the need for FULL POWER.

[Pete]

Hi and welcome.

Do a search, i know there is an affordable replacement part for it.
Do a search on the internet,i know Audi has a few but will need to change plug.

If you feel the need for full power all the time yank the secondaries.


Pete

[Jagdpanzer]

Welcome aboard Jeasen, you are definitely at the right place for ZR-1 support.
Jim Butler Chevrolet has LT5 secondary vacuum solenoid valves listed on ebay.
http://cgi.ebay.com/ebaymotors/90-95-CORVETTE-ZR1-LT5-SECONDARY-ACTUATOR-VALVE-ZR-1_W0QQitemZ370237770702QQcmdZViewItemQQptZMotors_C ar_Truck_Parts_Accessories?hash=item5633e40bce&_trksid=p4506.c0.m245

There maybe more sources available that other members are aware of.

[secondchance]

First I want to introduce myself, I use the screen name of Jeasen and I am new to this board. I am also a new ZR1 owner (1990 Red on Red). Although I have owned, maintained and drag raced Buick Grand Nationals for years this is my first ZR1.

I want to thank all the ZR1 guys that have gone before me and say Thank You for all the information available on the ZR1. The information is very valuable to a new owner. I was able to diagnose and repair my fuel pump problem for the cost of a couple of metal clamps. Thanks again for the help available in the How To section.

I am now trying to fix my Vacuum Problem and get the secondaries working. I started diagnosing the problem last night using information available on this board. It was not long and I found that the plenum needed to be removed. Once the plenum was removed I started checking the vacuum lines in different places. The plastic vacuum lines and the rubber connectors were all good. The actuators are both good (I was using a vacuum pump). The problem is the Vacuum Solenoid (Part #1999222).

Now my problem, I called the Chevy Dealer and the part is no longer available. I would like to know if one of you guys know of a replacement part that would work??? If not can I just remove this part and jumper the vacuum lines??? What has been you experience?? I feel the need for FULL POWER.

Welcome to ZR-1 community!
Is this what you are talking about?
http://www.whiteracingproducts.com/index.php?main_page=popup_image&pID=279
I realize part number is different but not sure which specific part you are looking for.

[secondchance]

Welcome aboard Jeasen, you are definitely at the right place for ZR-1 support.
Jim Butler Chevrolet has LT5 secondary vacuum solenoid valves listed on ebay.
http://cgi.ebay.com/ebaymotors/90-95-CORVETTE-ZR1-LT5-SECONDARY-ACTUATOR-VALVE-ZR-1_W0QQitemZ370237770702QQcmdZViewItemQQptZMotors_C ar_Truck_Parts_Accessories?hash=item5633e40bce&_trksid=p4506.c0.m245

There maybe more sources available that other members are aware of.

Got to be one or the other.
Neither match the part number 1999222.:icon_scra

[QB93Z]

Hello and Welcome to the NetRegistry Forum.

I got a Secondary Throttles Actuator Valve from Butler Chevrolet last month. It fit perfectly in George's 1990 ZR-1. GM Part #197222.

Jim

[jeasen]

I got the part number off this forum. It is listed in the vacuum repair at the top of the How To section. The part I need is the part that secondchance listed the link to. It is the part that is for sale on Ebay. The electric vacuum solenoid.

But, I am wondering about the suggestion to yank the secondaries. If this is an option that will not cause more problems then I like it. It seems to me that a whole series of plastic vacuum lines, rubber connectors, actuators, and solenoids are going to be nothing but trouble on a 20 year old car. I know this option would eliminate the power key function but I do not see that as a problem.

I would probably leave everything in place but just wire the secondary butterflies open. That way I would not be removing original parts. I would just be altering the function of the parts.

Are you guys sure that wiring the secondary butterflies open will not cause codes to set in the computer or cause problems with the operation of the motor???? If there is not a problem with doing this then this is what I am going to do.

Thanks for all your responses and offers of help. I am glad to now be a part of your ZR1 community.

Jeasen

[XfireZ51]

I got the part number off this forum. It is listed in the vacuum repair at the top of the How To section. The part I need is the part that secondchance listed the link to. It is the part that is for sale on Ebay. The electric vacuum solenoid.

But, I am wondering about the suggestion to yank the secondaries. If this is an option that will not cause more problems then I like it. It seems to me that a whole series of plastic vacuum lines, rubber connectors, actuators, and solenoids are going to be nothing but trouble on a 20 year old car. I know this option would eliminate the power key function but I do not see that as a problem.

I would probably leave everything in place but just wire the secondary butterflies open. That way I would not be removing original parts. I would just be altering the function of the parts.

Are you guys sure that wiring the secondary butterflies open will not cause codes to set in the computer or cause problems with the operation of the motor???? If there is not a problem with doing this then this is what I am going to do.

Thanks for all your responses and offers of help. I am glad to now be a part of your ZR1 community.

Jeasen

Jeasen,

I have mine tie wrapped open although I did remove the throttle plates.
The code is set with the ECM seeing the incorrect conditions for opening or closing the throttle, ie is there enough vacuum. That is controlled by the signal from the Differential MAP sensor. It can essentially be bypassed either mechanically or electrically so the ECM always sees the necessary vacuum. The calibration would be modified to run with secondaries always open except for idle.

[secondchance]

I got the part number off this forum. It is listed in the vacuum repair at the top of the How To section. The part I need is the part that secondchance listed the link to. It is the part that is for sale on Ebay. The electric vacuum solenoid.

But, I am wondering about the suggestion to yank the secondaries. If this is an option that will not cause more problems then I like it. It seems to me that a whole series of plastic vacuum lines, rubber connectors, actuators, and solenoids are going to be nothing but trouble on a 20 year old car. I know this option would eliminate the power key function but I do not see that as a problem.

I would probably leave everything in place but just wire the secondary butterflies open. That way I would not be removing original parts. I would just be altering the function of the parts.

Are you guys sure that wiring the secondary butterflies open will not cause codes to set in the computer or cause problems with the operation of the motor???? If there is not a problem with doing this then this is what I am going to do.

Thanks for all your responses and offers of help. I am glad to now be a part of your ZR1 community.

Jeasen

I saw the same on ebay for $89. That is not a bad price.
As for tying the secondaries open, theoretically intake at low rpm will slow down due to twice as large intake cross section area. In turn this could hamper ideal fuel vaporization resulting in reduced torque. Also, if I understand XfireZ51 correct, it may require recalibrated chip.
I know some have removed or fixed 2ndary port plates open. As for quality of idle, effect on low end torque and whether this mod require custom chip or not I am not very familiar.

If you do replace vacuum actuators be aware it can be installed incorrect (180 degree rotated) accidentally resulting in binding. I heard some later LT5s had this mistake at factory.

[secondchance]

I got the part number off this forum. It is listed in the vacuum repair at the top of the How To section. The part I need is the part that secondchance listed the link to. It is the part that is for sale on Ebay. The electric vacuum solenoid.

But, I am wondering about the suggestion to yank the secondaries. If this is an option that will not cause more problems then I like it. It seems to me that a whole series of plastic vacuum lines, rubber connectors, actuators, and solenoids are going to be nothing but trouble on a 20 year old car. I know this option would eliminate the power key function but I do not see that as a problem.

I would probably leave everything in place but just wire the secondary butterflies open. That way I would not be removing original parts. I would just be altering the function of the parts.

Are you guys sure that wiring the secondary butterflies open will not cause codes to set in the computer or cause problems with the operation of the motor???? If there is not a problem with doing this then this is what I am going to do.

Thanks for all your responses and offers of help. I am glad to now be a part of your ZR1 community.

Jeasen

I saw the same on ebay for $89. That is not a bad price (at least relative to $109 I see elsewhere).
As for tying the secondaries open, theoretically intake at low rpm will slow down due to twice as large intake cross section area. In turn this could hamper ideal fuel vaporization resulting in reduced torque. Also, if I understand XfireZ51 correct, it may require recalibrated chip.
I know some have removed or fixed 2ndary port plates open. As for quality of idle, effect on low end torque and whether this mod require custom chip or not I am not very familiar.

If you do replace vacuum actuators be aware it can be installed incorrect (180 degree rotated) accidentally resulting in binding. I heard some later LT5s had this mistake at factory.

[jeasen]

I got busy at work and was not able to check back until now. After reading the posts in regards to bypassing the vacuum system I decided I would buy the vacuum solenoid that was listed on Ebay.

However, when I went to buy it it was already sold.

I did not like the idea about losing torque. Torque is important to me that is why I have turbo Buicks and drive a diesel pickup.

Does anyone know about the other replacement solenoids that was mentioned? In the mean time I am going to see if I can my solenoid working.

I want to thank everyone again for their help.

[secondchance]

I got busy at work and was not able to check back until now. After reading the posts in regards to bypassing the vacuum system I decided I would buy the vacuum solenoid that was listed on Ebay.

However, when I went to buy it it was already sold.

I did not like the idea about losing torque. Torque is important to me that is why I have turbo Buicks and drive a diesel pickup.

Does anyone know about the other replacement solenoids that was mentioned? In the mean time I am going to see if I can my solenoid working.

I want to thank everyone again for their help.

That is just my thought based on my understanding. Others may have different opinion.

More expensive but worst case scenario - http://www.whiteracingproducts.com/index.php?main_page=product_info&products_id=279

[lbszr]

I got busy at work and was not able to check back until now. After reading the posts in regards to bypassing the vacuum system I decided I would buy the vacuum solenoid that was listed on Ebay.

However, when I went to buy it it was already sold.

I did not like the idea about losing torque. Torque is important to me that is why I have turbo Buicks and drive a diesel pickup.

Does anyone know about the other replacement solenoids that was mentioned? In the mean time I am going to see if I can my solenoid working.

I want to thank everyone again for their help.

I thought rock auto or auto zone listed the solonoid at one one time but couldn't find it now.

If you still are thinking about deactivating them Marc Haibeck could give you the different options and burn the chip. Mine are deactivated but still require the solonoid to be electrically connected, so if yours is broke electrically you still might have a problem. Marc might have a way completely disconnect the solonoid by now though maybe.

I've heard torque loss is about 10lbs. But I can't feel it. With a stock chip and a vacum guage T'd in while driving around mine opened before 2000 before deactivating. Good Luck.

[Pete]

Tthe secondaries are open anytime you go WOT no matter what RPM.

Also about loosing low end torque if you do it's very little to none.

Does anybody have a before and after Dyno #'s.

My experience with removing secondaries with huge ported intake ports drive's better from a stop.
It feels like i cranked the timing.
My throttle response is amazing i would go as far as to say it's better then stock.

Ask those who have removed them the rest is theories.

Trust me if my Z coughed sputtered or lost power i'd put them back on
in a heartbeat.

Pete

[LGAFF]

Guys at GM apparently did not think the secondaries were that important, look what they did with Snakeskinner, no secondaries! That car set the fastest 0-100-0 of any modern car tested at that time.

[XfireZ51]

Completely agree with Pete here. At least from my experience I have not felt or measured any loss of low end torque. My setup has ported plenum and matched head ports with throttle plates removed. With street tires it is difficult to leave from the line at anything higher than idle without spining the tires. They also break loose from a roll in second at 15-1600 rpm. IMO, secondaries were there for the valet key more than low end torque. Having said that, tuning is a prereq to optimize for it.




Tthe secondaries are open anytime you go WOT no matter what RPM.

Also about loosing low end torque if you do it's very little to none.

Does anybody have a before and after Dyno #'s.

My experience with removing secondaries with huge ported intake ports drive's better from a stop.
It feels like i cranked the timing.
My throttle response is amazing i would go as far as to say it's better then stock.

Ask those who have removed them the rest is theories.

Trust me if my Z coughed sputtered or lost power i'd put them back on
in a heartbeat.

Pete

[John Boothby]

I got busy at work and was not able to check back until now. After reading the posts in regards to bypassing the vacuum system I decided I would buy the vacuum solenoid that was listed on Ebay.

However, when I went to buy it it was already sold.

I did not like the idea about losing torque. Torque is important to me that is why I have turbo Buicks and drive a diesel pickup.

Does anyone know about the other replacement solenoids that was mentioned? In the mean time I am going to see if I can my solenoid working.

I want to thank everyone again for their help.
Jeasen, I have a spare solenoid if you want it. It is used, but I believe still works properly. I removed it a couple of months ago when I replaced my entire secondary vac system.

PM me if interested. Just pay shipping.

[jeasen]

John Boothby, PM sent.

[billybaloneey]

Jeason,

Jim Butler Chevy, in St. Louis MO, places what you need on eBay from time to time...they have some up for auction now...or you might just contact them directly.

[John Boothby]

I also have a brand new secondary solenoid GM pn: 1997201 for a 91-95 ZR-1. This part came in a kit ordered from White Racing a couple of months ago. He included two solenoids, one for the 90 and one for 91-95. Since I have a 90 I do not need the 91-95 solenoid. I am only selling on this forum. A brother's price is what is on the box: $38.17 plus shipping.

[Jagdpanzer]

Butler has another LT5 secondary solenoid valve up for auction:

http://i20.ebayimg.com/05/i/001/2c/0e/a7eb_35.JPG

http://cgi.ebay.com/ebaymotors/90-95-CORVETTE-ZR1-LT5-SECONDARY-ACTUATOR-VALVE-ZR-1_W0QQitemZ220462864169QQcmdZViewItemQQptZMotors_C ar_Truck_Parts_Accessories?hash=item33549c5729&_trksid=p4506.c0.m245

[Paul Workman]

I'll add my dittos to pulling the secondaries. If there is a loss of torque, I am oblivious. This is partly b/c I pulled the secondary hardware entirely as part of a top-end porting project. Like Dominick (and others with similar mods)...the damn tires have lots of trouble sticking in first OR second gear!

As for normal driving, I have to say it is better than stock. Like Pete mentioned, I love the new throttle response too. FWIW, the prototype 475 hp LT5 that was intended for the 95 MY, and later sidelined before it went into production, scrapped the dual runner bit all together; AND GM went with a single injector! I couldn't say whether the fact that so many have had superb results by siamesing part or all of the twin runners had any influence on the 475 hp LT5's intake system, but one can't help but see the similarities!;)

Secondaries: Parts that don't exist, seldom break. And! They don't cost much!:sign10:

P.

[scottfab]

Occasionally I have to let someone else drive my car. I chose to leave the secondary design in place so I can put the car in valet mode and take the key out. I also have an electrical actuator for the secondaries that I put together 7 yrs ago. The plan was to replace the vacuum system the next time it failed or I had to get under the plenum. Problem is, the vacuum system has not failed again.
But if I do mod the secondaries I will save all part (as I did with the exhaust). If I ever sell the car and the new owner wants to, the car can be made to be stock again.
Who knows, maybe the new owner would want to carve out the dash for a new sound system, chop the top down and put flames on the side. But the option for returning to stock will be possible.

[jeasen]

First I want to thank everyone for theire replies and help in regards to my post. I tied the secondaries open and put the plenum back on and doubled checked to make sure everything was connected and in place. After I refilled the cooling system I got in and tried to start it up. And guess what! The car would not start. It turned over but would not start.
My first thought was that I must have not got one of the electrical connections plugged into the ignition module correctly. So I quit working on the car and went into the house to contemplate. After thinking about the car not starting for a while I decided to check the fuses. Sure enough, the one marked instr was blown. I must of did this when I was trying to check out the vacuum solenoid.
I picked up some fuses yesterday and put a new fuse in and the car started right up.
I drove it around quite a bit today and I now know what full power feels like. The car pulls really hard above 4000 RPMs and revs to red line without a problem.
All I can say is that I am impressed.
Thanks again everyone for all your help and comments.
Jeasen:thumbsup:

[lbszr]

First I want to thank everyone for theire replies and help in regards to my post. I tied the secondaries open and put the plenum back on and doubled checked to make sure everything was connected and in place. After I refilled the cooling system I got in and tried to start it up. And guess what! The car would not start. It turned over but would not start.
My first thought was that I must have not got one of the electrical connections plugged into the ignition module correctly. So I quit working on the car and went into the house to contemplate. After thinking about the car not starting for a while I decided to check the fuses. Sure enough, the one marked instr was blown. I must of did this when I was trying to check out the vacuum solenoid.
I picked up some fuses yesterday and put a new fuse in and the car started right up.
I drove it around quite a bit today and I now know what full power feels like. The car pulls really hard above 4000 RPMs and revs to red line without a problem.
All I can say is that I am impressed.
Thanks again everyone for all your help and comments.
Jeasen:thumbsup:

Glad to hear you felt the lt5. Did you burn a new chip? It might need the sec inj. on sooner if not , could be more poewer to be had!

[jeasen]

No, it is the same chip. I can not give you an idea of the difference. The secondaries never worked since I started driving the car a couple of weeks ago.

I have nothing to compare it to, but it would be my guess that the vacuum operated secondaries would be a smoother transition between normal and full power.

[LT5-1935]

ACDelco 1997222 Accumulator Assembly Amazon.com $24.67 new