- classifieds - forums

Go Back Forums > Models > Saturn S-Series > S-Series Tech

Thread Tools Display Modes
Prev Previous Post   Next Post Next
Old 12-04-2021, 09:12 PM   #11
Master Member
billr is a splendid one to beholdbillr is a splendid one to beholdbillr is a splendid one to beholdbillr is a splendid one to beholdbillr is a splendid one to beholdbillr is a splendid one to beholdbillr is a splendid one to behold
Join Date: Jul 2013
Posts: 7,023
Default Re: specifics on compression testing, P0301

STFT was between -33 and -36
I can't really say whether this is good without knowing what the units are. If that is "-33" as a raw value ranging from -127 to +127 (a common 8-bit range), it OK. If, however, it is -33% of theoretical fuel required, it is a significant rim, something to be investigated, but still not a definite problem.
LTFT was -17.2 (Are these good values?)
Same problem here, units unknown. However, if this is percentage, it is probably too much.
MAP sensor was reading 9 inches of mercury, a vacume guage had read 34 inches of mercury previously in the same hole (is the sensor bad?)
9" Hg is pretty normal, about equal to 21" Hg on a vacuum gauge. Since no vacuum much past 30" Hg is even possible, I question the gauge. In fact, I wonder why they even bother with numbers beyond 30" on the dial...
O2 sensor 1 reading fluctuates between about 0.35V, and 0.75V
That range is normal, but we need to know the rate; and you need to correlate the sensor reading changes to STFT
O2 sensor 2 reading fluctuates between about 0.28V, and 0.68V (are the sensors bad? What do good readings look like?)
Same comment
spark ADV was between 16 and 20 (Does this matter?)
Spark advance certainly matters. but that range and variation seems about right for idle
TPS was 0%, I was not touching the throttle
O2 sensor readings are listed again for some reason, with the same values, except they are positive
STFT was listed again as sensor 2, 99.2% (Does that represent the amount of air, or fuel?)That would be fuel, a percentage of theoretical fuel required for the current engine running conditions (rpm, MAP, CLT, IAT

What specific problems are you trying to solve now? A recap or update, please, it has been a long thread.
billr is offline   Reply With Quote


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
How-To: Compression testing w/ engine out of car ShawnV How-To Library 6 10-14-2010 11:42 PM
2001 SOHC P0301 - confusing compression numbers BobbyBeans S-Series Tech 44 05-24-2010 11:34 AM
compression testing results Amp67 S-Series Tech 3 05-27-2009 01:54 PM
Testing Compression in an S-Series Saturn-Eh! How-To Library 20 10-13-2005 03:54 PM
Compression and Leak Down testing. Red97sc2 S-Series Tech 2 04-09-2004 02:37 AM

All times are GMT -4. The time now is 04:20 AM.

Advanced Forum Search | Advanced Photo Search

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2023, vBulletin Solutions Inc. The Saturn Enthusiasts Site.