Can someone look over this video and results with me about vacuum test/compression - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

spools420a · 05-25-2020, 10:19 AM

Note this is my gf 2004 kia rio but the kia forums dont have as much skilled eople as zilvia.The car has a misfire around idle I have been chasing and trying to fix.I did a vacuum test and compression test to see if the engine is ok.

heres the vid of the vacuum test
https://www.youtube.com/watch?v=SY34...ature=youtu.be

So with a/c off it seems good,we see 22in of vaccum BUT when the a/c kicks on we start seeing 15in of vacuum?when the a/c is on is when the car shaking seems worst.I do see very slight fluxuation of the needle but its so slight I dont see it as a problem.

the compression test results
dry
1# 150
2# 149
3 143
4 #150
wet
1# 182
2# 175
3 170
4 180

with this said can I rule out the engine low compression being the cause of misfire?

S14rebuild · 05-25-2020, 10:36 AM

Replace coil packs, wires and plugs....there cheap and will resolve the problem.

Yes ur compression is just fine

Kingtal0n · 05-27-2020, 03:30 PM

yep sounds like needs a tune up and a cleaning

jedi03 · 05-29-2020, 10:23 AM

+1 compression is good...hows the leakdown?

05-25-2020, 10:19 AM	#1
spools420a Zilvia Junkie Join Date: Dec 2009 Location: phoenix az Age: 42 Posts: 460 Trader Rating: (1) Feedback Score: 1 reviews	Can someone look over this video and results with me about vacuum test/compression Note this is my gf 2004 kia rio but the kia forums dont have as much skilled eople as zilvia.The car has a misfire around idle I have been chasing and trying to fix.I did a vacuum test and compression test to see if the engine is ok. heres the vid of the vacuum test https://www.youtube.com/watch?v=SY34...ature=youtu.be So with a/c off it seems good,we see 22in of vaccum BUT when the a/c kicks on we start seeing 15in of vacuum?when the a/c is on is when the car shaking seems worst.I do see very slight fluxuation of the needle but its so slight I dont see it as a problem. the compression test results dry 1# 150 2# 149 3 143 4 #150 wet 1# 182 2# 175 3 170 4 180 with this said can I rule out the engine low compression being the cause of misfire?

05-25-2020, 10:36 AM	#2
S14rebuild BANNED Join Date: May 2019 Location: Florida-FAIL Posts: 2,495 Trader Rating: (8) Feedback Score: 8 reviews	Replace coil packs, wires and plugs....there cheap and will resolve the problem. Yes ur compression is just fine

05-27-2020, 03:30 PM	#3
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 41 Posts: 4,828 Trader Rating: (17) Feedback Score: 17 reviews	yep sounds like needs a tune up and a cleaning

05-29-2020, 10:23 AM	#4
jedi03 Nissanaholic! Join Date: Jul 2008 Location: albuquerque Posts: 1,836 Trader Rating: (8) Feedback Score: 8 reviews	+1 compression is good...hows the leakdown?