Nfire247

ok, so here is the deal. I bought a 1997 dx 2dr. swapped to a b16a(1994 sir i believe) it came with some preblems. 1st, 24mpg and a CEL for MAP and TPS, i replaced both and the cel went away. Vtec now works, but at 5500rpm, im pretty sure its supposed to be closer to 4500... i still get only 24 mpg. I believe that the guy who did the swap was lazy and stupid, so its very possible that he just forgot something. I have already found a missing trans. mount and a missing vaccume line (throttle body to char. canister) so let me know anything that might get me these preblems.

i have also checked the ecu for a chip, and couldnt find one.
thanks

Nfire247

it has also been swapped from an auto. to manual trans.

93egSLEEPER

vtec at 4500 is pretty low... 5500 is close to stock which is 5800. as for the gas mileage 24 is normal if your foots on the floor constantly around town.... i get 26 around town mixed driving. highway i get 31 though. it may need a tune and all that to figure out all the A/F ratios.

B serious

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93egSLEEPER &raquo;</TD></TR><TR><TD CLASS="quote"> it may need a tune and all that to figure out all the A/F ratios.</TD></TR></TABLE>

It doesn't need a tune to run right if the engine is close to stock with a stock ECU. If it's modded (more than bolt ons), it might need a tune.

b16a vtec is at around 5800 with a stock ECU. The B18C1 (GSR) is the only B series that has 4500 RPM vtec stock.

24MPG could just be your driving habits. It's not THAT far off of where it should be. It should be around 28-30 around town and 30-35 highway. That's usually what I got in my 99 hatchbox with a b16a, and that's what I get in my 99 GSR.

Do you floor it a lot? It sounds like you might. Do you let the car idle a lot? do you unnesscarily let it warm up in the morning? Do you make a lot of short, cold trips? Use shitty gas?

Try a plug/wire/air filter tune up. Try a new O2 sensor. Those are all good maintainence ideas anyway.


If your swap wasn't done correctly, you will lose MPG..so just double check all the vacuum lines if you say that some of them were in the incorrect place. Especially the vacuum line from the FPR to the manifold. Make sure it's present with no holes in it.

You sure the MAP and TPS codes weren't being thrown because you just mixed up the connectors? This happens a lot. Maybe when you replaced the sensors, you switched the connectors around to the right places. The MAP and TPS have the an identical plug design.

packman5280

when i run hard in my 2000 si in the city i get around 26, long cruising trips on the highway i get 36.

Syndacate

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by packman5280 &raquo;</TD></TR><TR><TD CLASS="quote">when i run hard in my 2000 si in the city i get around 26, long cruising trips on the highway i get 36.</TD></TR></TABLE>

No you don't.

36 @ highway cruising speeds in your EM1? LoL - KK

@ OP: As others have suggested this could simply be a matter of how you drive, as that will indeed affect your gas mileage. Though if you consider the lower gas mileage and combine that with the half assed job that was done putting the motor in, then combine both of those with the low VTEC engagement point, it all points to an ECU discrepancy.

On the driver's floor kick panel, see which ECU they used.

To tell an ECU code, it's the numbers in the middle, ie:
XXXXXXXXXXXX-P28-XXXXXXXXXXXX
Something like that - tell us what's in the middle, b/c it sounds like you're rocking the wrong ECU, and if the swap was done as sloppily as you say, it wouldn't surprise me if he's running a P2P or a shitty chipped OBD-I. Go analyze the situation under there, see what's up, and hit us back.

EDIT:
Also, this could just be a topographical issue. See the B16 doesn't have much torque, so when driving around sometimes you have to lay on it a bit to make it move.

Question: How's your fuel mileage if you do a whole trip and say, don't go above 4500 RPM?

raphael

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B serious &raquo;</TD></TR><TR><TD CLASS="quote">

It doesn't need a tune to run right if the engine is close to stock with a stock ECU. If it's modded (more than bolt ons), it might need a tune.

b16a vtec is at around 5800 with a stock ECU. The B18C1 (GSR) is the only B series that has 4500 RPM vtec stock.

24MPG could just be your driving habits. It's not THAT far off of where it should be. It should be around 28-30 around town and 30-35 highway. That's usually what I got in my 99 hatchbox with a b16a, and that's what I get in my 99 GSR.

Do you floor it a lot? It sounds like you might. Do you let the car idle a lot? do you unnesscarily let it warm up in the morning? Do you make a lot of short, cold trips? Use shitty gas?

Try a plug/wire/air filter tune up. Try a new O2 sensor. Those are all good maintainence ideas anyway.


If your swap wasn't done correctly, you will lose MPG..so just double check all the vacuum lines if you say that some of them were in the incorrect place. Especially the vacuum line from the FPR to the manifold. Make sure it's present with no holes in it.

You sure the MAP and TPS codes weren't being thrown because you just mixed up the connectors? This happens a lot. Maybe when you replaced the sensors, you switched the connectors around to the right places. The MAP and TPS have the an identical plug design.



</TD></TR></TABLE>why do you say it is uneccesary to let the engine warm up in the mornings


Modified by raphael at 10:41 AM 12/27/2007

packman5280

"No you don't.

36 @ highway cruising speeds in your EM1? LoL - KK"

uh yeah, i do. drove from carbondale co to aurora co in 3 hours, averaging 80-85 mph, one stop in idaho springs on the way, don't remember the exact amount of gas i put in but the math said 36mpg (maybe it was 35.7 or something like that). so mountain driving too, chasing an A4 up vail pass at 7k for a ways too. maybe you were there and could tell me what mpg i really got?

Syndacate

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by packman5280 &raquo;</TD></TR><TR><TD CLASS="quote">"No you don't.

36 @ highway cruising speeds in your EM1? LoL - KK"

uh yeah, i do. drove from carbondale co to aurora co in 3 hours, averaging 80-85 mph, one stop in idaho springs on the way, don't remember the exact amount of gas i put in but the math said 36mpg (maybe it was 35.7 or something like that). so mountain driving too, chasing an A4 up vail pass at 7k for a ways too. maybe you were there and could tell me what mpg i really got?</TD></TR></TABLE>

I wasn't there, but yeah, I can definitely tell you you weren't pulling 36mpg with a B16 UP HILL at 85 mph.

GTFO, plz.

Learn to use a calculator or gtfo.

(Probably one of these geniuses which waits until it gets to half a tank then tries dividing 10.9 by two and using that )

Nfire247

well thanks for clearing up the vtec question, i was basing it off a gsr, so glad to see that its not a problem. As far as my driving habits, i hardly ever am in vtec daily driving, usually shift around 3000, at about a 1/4 throttle, so i would like to think that its not my driving methods. plus i took it to the track a while back and avg'd about 25mpg that tank... weird.
ill check the ecu as soon as i go outside. its supposed to be a p28 correct?
thanks guys, let me know if you think of anything else.

packman5280

yep you got me. i can't use a calculator, and you know what kind of mileage i get better than me. of course i wasn't pulling 36 uphill at 85. but i was doing much better than 36 on the long downhills coasting for miles. that why it's called an average. i'm not retarded, i can figure out my mileage. i was just trying to say that you get different mileage depending how and where you drive. go drink bleach.

Nfire247

plus i live in GA, so not much cold weather driving for me.

jdmcivicracer89

dam i got a 00 si and i only get about 20 mpg.. thats not beating on it...

Syndacate

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jdmcivicracer89 &raquo;</TD></TR><TR><TD CLASS="quote">dam i got a 00 si and i only get about 20 mpg.. thats not beating on it... </TD></TR></TABLE>

Then there was something wrong with it.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Nfire247 &raquo;</TD></TR><TR><TD CLASS="quote">well thanks for clearing up the vtec question, i was basing it off a gsr, so glad to see that its not a problem. As far as my driving habits, i hardly ever am in vtec daily driving, usually shift around 3000, at about a 1/4 throttle, so i would like to think that its not my driving methods. plus i took it to the track a while back and avg'd about 25mpg that tank... weird.
ill check the ecu as soon as i go outside. its supposed to be a p28 correct?
thanks guys, let me know if you think of anything else.</TD></TR></TABLE>

It's possible that the guy's running a chipped P28, but no, absolutely not.

It's supposed to be a P2T if memory serves me correctly.

Though keep in mind any OBD-I ECU can be chipped and ran to "emulate" any other ECU.

So I'd find a P2T that a friend has or something and plug it in for a week and see if the problem persists. I'm almost willing to bet money that the problem is A) The guy has the wrong ECU in there, or B) The guy has a chipped ECU that's tuned like crap

Lscivic1999

thats what im getting right now 24-26 mpg 75% city driving , bad spark plugs too..

usually in the Winter time here in Boston my mpg goes down a lil...

B serious

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by raphael &raquo;</TD></TR><TR><TD CLASS="quote">why do you say it is uneccesary to let the engine warm up in the mornings


Modified by raphael at 10:41 AM 12/27/2007</TD></TR></TABLE>

It's not a 1978 Ford. The manual from Honda says you do not have to warm up your vehicle. It's unnesacary. It's a fuel injected modern automobile. They dont have to be warmed up anymore. I get in, and drive. Then you drive slowly for the first few miles till it warms up. Then you drive normally. If it's an EXTREMELY cold day, I'd let it sit for maybe a few seconds...like 10 seconds. Then drive away.

Syndacate

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B serious &raquo;</TD></TR><TR><TD CLASS="quote">

It's not a 1978 Ford. The manual from Honda says you do not have to warm up your vehicle. It's unnesacary. It's a fuel injected modern automobile. They dont have to be warmed up anymore. I get in, and drive. Then you drive slowly for the first few miles till it warms up. Then you drive normally. If it's an EXTREMELY cold day, I'd let it sit for maybe a few seconds...like 10 seconds. Then drive away. </TD></TR></TABLE>

It's not necessary, just highly recommended that you keep the RPM very low (like under 2k low) until the engine reaches standard operating temperature.

High RPM on a cold block = block = owned

B serious

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Syndacate &raquo;</TD></TR><TR><TD CLASS="quote">

It's not necessary, just highly recommended that you keep the RPM very low (like under 2k low) until the engine reaches standard operating temperature.

High RPM on a cold block = block = owned</TD></TR></TABLE>

HIGH RPM use is bad. 2k....is a little extreme as a limit. I shift at like 3-4k...whatever feels right. I might try to keep it closer to 3 or so when the car is dead cold, but I live in illinois...not antarctica.

Nfire247

so my ecu is a p30... is that bad?

Italix

p30 is the sir2 ecu. Its the correct one. Do a tune up and be easy on the gas and you'll get close to 30mpg average.

Speed_1

you said that the motor was originally an Automatic. Did you switch the camshafts over to Manual? There is a differents in automatic cams and Manual cams in a B-series motor.

ComeOnKip

if there was any difference in the cams i would believe that the automatic cams would be more demure to net better mileage...no?

B serious

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Speed_1 &raquo;</TD></TR><TR><TD CLASS="quote">you said that the motor was originally an Automatic. Did you switch the camshafts over to Manual? There is a differents in automatic cams and Manual cams in a B-series motor.</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ComeOnKip &raquo;</TD></TR><TR><TD CLASS="quote">if there was any difference in the cams i would believe that the automatic cams would be more demure to net better mileage...no?
</TD></TR></TABLE>


B16As never came in automatic. His car was originally automatic. He had it converted to manual with the B16A swap.

I dont think the cams are any different automatic to manual on B series.

Syndacate

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B serious &raquo;</TD></TR><TR><TD CLASS="quote">

HIGH RPM use is bad. 2k....is a little extreme as a limit. I shift at like 3-4k...whatever feels right. I might try to keep it closer to 3 or so when the car is dead cold, but I live in illinois...not antarctica. </TD></TR></TABLE>

When the engine is ice cold 3k is the limit I use (2k was a typo) - obviously you can increase your cap as the engine warms up, but when it's ice cold (like you get in the car, and go), no warmup time, you shouldn't let it past 3k...All the roads around my campus are flat as hell so I can pretty much shift low - so I can do it b4 3k, usually, but then again, I don't have a tach anymore.

Nfire247

i did plugs about a month ago when i fixed the CEL, i bought a new airfilter last summer, im runnign a ram intake right now, could wires really help me 6 mpg?

also what about a new o2 sensor, i am running the skunk2 conversion harness, obd2-obd1 i believe. could any of this be a problam, and whats the fix?

i also paid attention to my driving today, my avg shift is closer to 3500 @ 1/4 to 1/2 throttle, but that still shouldn't be a problem right? i rarly hit vtec daily driving, i try to be nice...