My check engine light on my 1998 Prelude Base has come on because of the barometric pressure. Is there any other way to fix this issue other than replacing my ECU with another one?


I'm having a hard time finding a used California emission 5spd ECU and I don't want to spend $650 for a new one.

Can't use Hondata to get rid of it since it's an OBDII.

Thanks.

 

yea get a new baro/map sensor..i have one for a h23 but i think the part number for the firewall mounted one is the same.

 

so let me get this straight...it's not the ECU? Just a sensor?

I was looking at the Helm's manual and it mentioned changing the ECU...

 

its the map sensor...

 

barometric sensor is inside the ecu

 

That's what I thought.... so was my original assumption upon changing the ECU correct?

There is no other way to fix this?

 

oh didnt know it was in the ecu, guy over at honda told me to replace the BARO/MAP sensor...so i did and it fixed my CEL..well good luck with that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ZXRider &raquo;</TD></TR><TR><TD CLASS="quote">That's what I thought.... so was my original assumption upon changing the ECU correct?

There is no other way to fix this?</TD></TR></TABLE>

try http://www.car-part.com and look for a used ECU on there, its a website with junk yard across the nation, you can try and use california as the state for the search for a ECU.

it doesnt hurt to try and replace the map sensor either. thats pretty cheap

 

I had the same ecu code pop up a week back. I did buy a replacment ecu but when I was going to replace the old one I noticed that one of the connects wasnt pluged in all the way, I guess I didnt push it in enough when I removed my ecu before and it wiggled its way out. I pushed the plug back in, reset the ecu, and havent had a problem since. Im not saying that is your problem but you could always try.

 

Hmmm... I wonder if it's simply my MAP sensor.... I had to remove it during my cylinder head rebuilt and ended up stripping the phillips head on one of the screws that hold the MAP down to the TB... so the MAP is only held on currently with one screw..which is probably not that tight also, so maybe it's not getting an accurate reading?

 

having a bad map sensor can cause the ecu to inadvertently throw a baro code because it is based on a differential pressure reading between the map and baro sensors. so if the map sensor is outputting a reading thats way off, it can trick the ecu into thinking the baro pressure reading is wrong.

personally i would test out a known good map sensor first to see if that helps before sinking the money into a replacement ecu and having honda program the immobilizer and all.

or if you are good with soldering try sourcing a similar baro sensor from a spare ecu and swap it out of your current ecu.

 

Thanks Eddie. I'll have a friend of mine who owns a Prelude stop by and see if his MAP sensor will make a difference or not.

If it ends up being an ECU, I might just buy a spare ECU and have a TV repair shop or someone with soldering skills take out the sensor and put it on my old ECU.

 

If you can't get the on top of the TB mount to work, you can let the MAP dangle and just hook a vac line to it. Just make sure to plug the hole on the TB.

 

Could you please elaborate on that? I don't think I understand you.

Thanks.

 

since your screw or whatever is fubar, you can take the MAP off the top of the throttle body and just run a vac line to it and let it dangle behind the IM.

Then plug the hole it used to fill, a screw works well, just make sure to do that w/the tb off so u don't get metal shavings in the vac ports.

 

Oh gotcha. Intresting information, definitely useful. Although I don't need to do that since I was able to remove the screw completely. The screw head was stripped but I used a file to turn the screw into a flat head, then simply used a flat head screw driver and removed the screw.

I actually just stopped by the local hardware store and picked up two new screws to use and see maybe the MAP sensor was not sealed enough and was getting wierd readings. I highly doubt that is the case but oh well.