1990 zr1

[Willard]

My secondary port vacume pump cycles on and off but this does not seam to efect the performance of the car. My question is, why go to the trouble of replacing vacume lines when the pump will automatically provide the needed vacume?

 

[jonszr1]

because it mean your car has a vacume leak, that could cause your car to run very lean at cruize conditions .. have you investigated what it costs to rebuild an lt5 motor . 10k min.. you may not be getting full secondary operation costing you some power .if you get your gaskets from jerrys gaskets and utilize the knowledge base on the zr1 registry, you will find alot of people more than willing to help you fix what ever problems are going on with the car . its tooo rare a car not to take the time to fix her so she can give you years of what we call the perma grin plus why take the chance of burning a piston and a valve because you dont wasnt to handle the problem . but in the end its your car and only you can decide what you want to do . also i see you have a 90 and if you havent replaced the injectors you will more than likely have to in the near future as the 90-92 cars have injectors that will fail due to the ethanol in todays fuel . just wanted to give you a heads up on that . if you would like me to share in more detail about the lt5 motor pm me your ph number and time you would like me to call and i will be happy to go into more detail about this fine motor . owning 3 of these cars i have alot of experience with them .have a great day

 

[Hib Halverson]

If the pump cycles frequently, when the key is on and the engine is off, there can be times where the vacuum leak you have will allow the port throttles to close even if the pump is running.

Bottom line: fix the vacuum leak.

 

[Willard]

If the pump cycles frequently, when the key is on and the engine is off, there can be times where the vacuum leak you have will allow the port throttles to close even if the pump is running.

Bottom line: fix the vacuum leak.

Do you know of anyone in southern California that can do this type of work?

 

[jonszr1]

where in so cal do you live .? i might be able to come down and help you with it . i do have extra vacume parts and plenum gaskets . pm me if you would like to have me come take a peek .

 

[Willard]

Zr1

where in so cal do you live .? i might be able to come down and help you with it . i do have extra vacume parts and plenum gaskets . pm me if you would like to have me come take a peek .

Porterville John 760-880-4915

 

[jonszr1]

well just to update this thread , john and i replaced the prt throttle selinoid and vac canister and ck valve , put in a new set of ngk plugs, tightened the injector housings and she is back to running very nicely . we went to his favorite spot to try her out after we got done and he is now lovin this car and has that perma grin we all get when we go through the gears . his car is a very clean 90 with only 9k miles on her and still smells new inside .he and his lady are also 2 of the nicest people i have met, they tried to feed me the refridgerator the 2 times i came over . i do love that red metalic on these cars .so john welcome to the brotherhood ,its a pleasure making a new friend .

 

[jonszr1]

opps, i forgot we also put in a new set of injectors from ficinjectors and they worked perfectly .thanx again jon