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Roadster · 03-12-2017

Ok, could not contain myself any longer.....so the roads are halfway decent and I went for a ride with my new sparkplugs....I like them a lot.
Even though the cold temps @ 33* helps with power, I have to say these new plugs are extremely responsive. Pulls effortlessly through all the gears, feeling like more added power even besides the secondaries now being fully operational.

Now for a few slight (have to figure out) items....
1- Got into it in 1st gear getting the r's close to 5k, and it felt like the accelerator pedal kicked back towards my foot. Shifted into 2nd & 3rd, brought the r's up again, was fine. Tried it again after a mile or so, did not do it that time. All future heavy throttle in 1st gear did not duplicate the kickback. Thought that was kind of unusual....

2- I noticed that when the plenum pull was done, and the vacuum issues were addressed, when first turning the key to the on position to hear the vacuum pump, it only came on for about 2-3 seconds. Today when first started, it stayed on for 3-5 seconds. All repeat "hot" starts just turning the key to the on position did not activate the pump at all.

3- Reason #2 has me concerned is that the idle is still not quite right. And at one time today, it did go as high as 1200 r's when I came to a stop. Sometimes it will idle at 650-700 r's when stopped, other times it will be at 900-1000 r's when stopped.
If I am stopped with trans in 1st gear, and idle is higher and I let the clutch out slightly with my foot on the brake, as soon as the clutch starts to engage, the idle will drop to normal and stay there even as I press down on the clutch pedal to disengage.
I know that there may be a couple of things to look for, as has been mentioned before, such as: the throttle blades completely closing, or a slight vacuum leak due to a vacuum hose coming loose under the plenum. Although the digital camera showed everything looking good from before....

Engine runs great, the best since I have owned the Z, once the idle issue gets resolved, it will be complete.....at least for me!!!

03-12-2017	#28
Roadster Join Date: Mar 2014 Location: Warrington PA Posts: 1,914	Re: Changing the spark plugs..... Ok, could not contain myself any longer.....so the roads are halfway decent and I went for a ride with my new sparkplugs....I like them a lot. Even though the cold temps @ 33* helps with power, I have to say these new plugs are extremely responsive. Pulls effortlessly through all the gears, feeling like more added power even besides the secondaries now being fully operational. Now for a few slight (have to figure out) items.... 1- Got into it in 1st gear getting the r's close to 5k, and it felt like the accelerator pedal kicked back towards my foot. Shifted into 2nd & 3rd, brought the r's up again, was fine. Tried it again after a mile or so, did not do it that time. All future heavy throttle in 1st gear did not duplicate the kickback. Thought that was kind of unusual.... 2- I noticed that when the plenum pull was done, and the vacuum issues were addressed, when first turning the key to the on position to hear the vacuum pump, it only came on for about 2-3 seconds. Today when first started, it stayed on for 3-5 seconds. All repeat "hot" starts just turning the key to the on position did not activate the pump at all. 3- Reason #2 has me concerned is that the idle is still not quite right. And at one time today, it did go as high as 1200 r's when I came to a stop. Sometimes it will idle at 650-700 r's when stopped, other times it will be at 900-1000 r's when stopped. If I am stopped with trans in 1st gear, and idle is higher and I let the clutch out slightly with my foot on the brake, as soon as the clutch starts to engage, the idle will drop to normal and stay there even as I press down on the clutch pedal to disengage. I know that there may be a couple of things to look for, as has been mentioned before, such as: the throttle blades completely closing, or a slight vacuum leak due to a vacuum hose coming loose under the plenum. Although the digital camera showed everything looking good from before.... Engine runs great, the best since I have owned the Z, once the idle issue gets resolved, it will be complete.....at least for me!!! __________________ Tom 1994 ZR-1 #009 "captured test fleet car" 1974 LS4 454 Vert 1974 L-82 355 Vert. 1982 L83 CFI...now a retired "dd"....Sold WAZOO Member Last edited by Roadster; 03-12-2017 at 07:45 PM.