Timing 44 degrees at 4000rpm, 29 at 1600
#1
Timing 44 degrees at 4000rpm, 29 at 1600
Had my computer tuned and it idles at 1600 with 29 degrees of timing. If I rev it up to 4000 the timing goes to 44 degrees. The engine is a stock '04 LQ4 from a van in a 70 blazer. The tuner claims this is normal timing on these engines. Does this sound remotely correct?????? I'm assuming the advanced timing is causing my high idle problem.
#4
Without any load on the engine and just revving it up in P/N the timing does go way up--If you had it in gear and underway it would be way less--Try putting it in gear with your foot on the brake and rev it up as much as you can without it moving--then read the timing---it'll be 1/2 as much---
Thanks,
Jim
#5
Thanks,
#6
In drive under a load timing drops way down . Engine still misses, runs poorly and idles high. The Predator still shows 5 different codes:
P0101-MAF
P0315- Crank Shaft Position Not Learned
P0507- Idle control system, RPM higher than expected
P0522-Oil Pressure low (stock oil sender isn’t hooked up)
P2761- Minimum Idle Position not Learned
P0101-MAF
P0315- Crank Shaft Position Not Learned
P0507- Idle control system, RPM higher than expected
P0522-Oil Pressure low (stock oil sender isn’t hooked up)
P2761- Minimum Idle Position not Learned
#7
TECH Apprentice
iTrader: (14)
Join Date: Oct 2005
Location: Ewing, NJ
Posts: 372
Likes: 0
Received 0 Likes
on
0 Posts
I see 41-44 degrees of timing while cruising so that doesn't seem to be a problem. At idle I think it's lower like around 19 but I'll have to check again to be sure. The crank code sounds like the crank sensor isn't hooked up or working at all. And the idle sounds like the IAC may need to be cleaned in the throttle body or checked to make sure the IAC motor is working properly. Start with the crank sensor and see if you can find out why it's not reading anything, that could be messing with the timing and idle.
Trending Topics
#8
TECH Addict
iTrader: (6)
No, the timing is not causing your high idle. You can put the timing to 45* at idle and have it idle at 800 rpm if the IAC is doing its job, i've done it. It's either something else in the tune that was changed, or something mechanical like a vacuum leak or throttle body not closing all the way.
#9
TECH Addict
iTrader: (10)
Go to www.efilive.com and download the free trial version of software. Then open up a supplied tune or one from the website, and look at the spark tables, you will see what they look like stock..
#10
No, the timing is not causing your high idle. You can put the timing to 45* at idle and have it idle at 800 rpm if the IAC is doing its job, i've done it. It's either something else in the tune that was changed, or something mechanical like a vacuum leak or throttle body not closing all the way.
#11
TECH Addict
iTrader: (6)
Ok, the Iac is good but it's not doing what it's supposed to. Usually that happens when the throttle is just a little bit open (because the screw is adjusted too high), but enough that the pcm thinks you're holding the throttle open on purpose so it never goes into "idle mode" where the iac adjusts to get you to idle rpm. I don't know if that's your problem because of the missing and the codes though.
#12
Ok, the Iac is good but it's not doing what it's supposed to. Usually that happens when the throttle is just a little bit open (because the screw is adjusted too high), but enough that the pcm thinks you're holding the throttle open on purpose so it never goes into "idle mode" where the iac adjusts to get you to idle rpm. I don't know if that's your problem because of the missing and the codes though.
#13
The computer was not set up for the IAC. There was some confusion about the TB that I was using. I sent it back to Current Performance who worked on it and finally switched it with a different computer. The truck now runs 10x better then before.