14mpg :-( - Page 2

pavanbabut · #16 09-11-2010, 11:49 PM

Quote:

Originally Posted by STORMINORMAN

Did an 11k mile cross-country trip last year in the '92 and averaged an overall 28 mpg on regular unleaded. If you are getting 14 mpg something is definitely not right.

Good Luck &

Cheers!

I am interested in following this thread as I am also facing this mpg problem probably less than 14. Today it passed smog without a hitch like it did last time. For 95 and old, they do another test for fuel leak test which it passed too. If it is running rich, it would have failed the test. So, I guess the cats are taking all the beating of reducing the emissions.

92 SVX · #17 09-12-2010, 11:51 AM

interesting, I just moved and on the drive I averaged 22-24 this was all highway. 2 things I know 1 the spark plugs are bosh platinum but look worn, should not have caused a significant decrease though. and 2 its running full time 50/50 solenoid C is not getting power it appears. the FWD fuse does nothing.
This is what I believe is causing the drop in mileage.

laserx · #18 09-13-2010, 09:23 AM

Quote:

Originally Posted by laserx

Talking of 02 sensors issues, I've got a strange one. Got 02 and knock sensor codes back from a CEL. Replaced them both all was good for 12 days then the 02 code comes back. Take it back to the dealer, new plugs (had 100km) and gaskets for the exhaust to insure no leaks. 13 days later 02 code again. Back to the dealer, he wants me to buy a new MAF, even though there is nothing to indicate there is a problem with it. They will not consider that perhaps they got a defective 02 sensor. The car drives perfectly with the CEL on, idles perfectly, not a single issue except I'm sick of seeing the CEL on every two weeks....any ideas as to where to start looking or should I just make the order another 02 senor and see if it comes back on?

My engine seems to have fixed it's self? Thursday filled up with 94 octane and added a bottle of Lucus Gas additive, within 60 miles the check engine light turned off? Haven't seen it since....hope it stays this way, between, ture up, pulling engine to fix oil leaks, and rebuilding the transmission, I'm in over $6k this year in repairs....sure hope that's it for this year.

pavanbabut · #19 09-13-2010, 09:28 AM

Quote:

Originally Posted by laserx

My engine seems to have fixed it's self? Thursday filled up with 94 octane and added a bottle of Lucus Gas additive, within 60 miles the check engine light turned off? Haven't seen it since....hope it stays this way, between, ture up, pulling engine to fix oil leaks, and rebuilding the transmission, I'm in over $6k this year in repairs....sure hope that's it for this year.

Just a suggestion, while you were doing all that, you should have done this too. When I am doing tune up on mine, I am gonna do this one too.

TomsSVX · #20 09-13-2010, 05:06 PM

Poor mileage, new 02 sensors, and other monitoring sensors reading properly leads me to believe injector(s). If a fuel injector hangs or does not atomize properly it will run rich and throw 02 sensors codes because the adjusting trim for the bank is outside of spec.

For example, say the #1 cylinder is hanging its injector and always injecting too much fuel. There is not a good monitoring system to detect the issue, so all the ECM sees is that the bank is running rich. The ECM will change the injection on the whole bank to trim it back but the simple fact is, the bank is still running rich no matter the trim of fuel. The ECM sees this and can only blame the 02 sensor for not reading properly. Once this happens the default fuel map is put into place which tends to run the engine rich to make sure it does not run lean (remember the ECM thinks the 02 sensor is FUBAR).

It is at this point you need to pull the plugs and inspect them for irregularities in the cylinder's combustion. Try to isolate the injector(s) causing the issue and replace them. My personal opinion would be to replace all 6 injectors because they are now 15+ years old and not working as well as they could be

Tom

laserx · #21 09-15-2010, 11:34 AM

Quote:

Originally Posted by pavanbabut

Just a suggestion, while you were doing all that, you should have done this too. When I am doing tune up on mine, I am gonna do this one too.

Thanks, looks like I'll have to try something more as my CE light that turned its self off has now turned back on....Hate seeing that dammed light on my dash. I just printed off the instructions your link lead to, so now to convince my son to take it to his shop and do as the instructions say. I'm not going back to my Dealer as the mechanic there, wants to swap out the MAF as his solution. Such a strange issue intermittent CEL, turns it's self on and off when it feels like it....or should I say when a mystery set of circumstances happen it turns on and then off a few days later, then on again....driving me crazy.

SoCal LS-L · #22 09-15-2010, 05:45 PM

If I were in your shoes id buy the NGK O2's from Advance online for $50 each. The fact that your ECU keeps kicking on and off the O2 code tells me it doesnt like the brand you bought, or theres a defective one. You never answered which type you bought.

Huskymaniac · #23 09-15-2010, 06:29 PM

Quote:

Originally Posted by SoCal LS-L

If I were in your shoes id buy the NGK O2's from Advance online for $50 each. The fact that your ECU keeps kicking on and off the O2 code tells me it doesnt like the brand you bought, or theres a defective one. You never answered which type you bought.

This one was suggested to me on the "other" site:

http://www.amazon.com/Bosch-13250-Ox.../dp/B000BZEHBC

kwren · #24 09-15-2010, 07:18 PM

Quote:

Originally Posted by Huskymaniac

This one was suggested to me on the "other" site:

http://www.amazon.com/Bosch-13250-Ox.../dp/B000BZEHBC

I put the Bosch one on of my SVX's about 3 years and 40,000 miles ago and have had no more codes, but mine actually needed one!

I would think that any good brand would work fine if it was actually needed... most things we buy are not manufactured by the company that "paints their name on the box", even if purchased from a dealer,but are pretty much generic.

Keith

laserx · #25 09-16-2010, 09:29 AM

Two months ago I had the dealer install new NGK Laser Platinum plugs, as part of a tune up, so unless he messed up on the install, plugs should not be the issue. I'm now leaning towards it being an injector issue. I am assuming the car is relearning as it runs, once it runs fine for a certain amount of time, it drops the CE (02 sensor) and clears it it's self. Then an injector malfunctions long enough to bring the code back, then repeats over and over. Then again it could be anything....still chasing the symptoms, now to find the cause.

Hondasucks · #26 11-21-2010, 09:13 PM

I've got new NGK Platinum plugs, I resoldered the MAF and added an engine ground (if I plug the Select Monitor in and watch the graphs, I keep seeing random spikes to 5V on the MAF and the TPS, but they're so quick you can't catch them most of the time) it turns over faster and seems to run better, got 20mpg on my last run to Vancouver (oddly though, I used a quarter of a tank getting there and I used a half a tank coming back...) but in town I'm still getting crap. For sensors I bought OEM ones, I will try the CTS and see if that helps :-)