My new project :D (rebuilding 1989 Honda CRX HF - considering VX engine swap)

[wyatta4]

Here are some photos of the MPGuino


Temporary location in the ash tray..


I know I know I know you're going to say "Ahhhh, he soldered straight to the MPGuino." Just stop. Everything is going to be alright. It's better this way and it works for my mounting location.


I used the phone jack idea found in another thread on here.. It works great! I stole the small jack thats soldered to the MPGuino from my Bedroom and bought the other one along with the cord at Walmart.. I had to, Radioshack was out of them...

I will clean up the wires once I am done with the initial calibration.



Here is my constant.. I dont know what that thing is called that I used but it is very nifty. Found it somewhere...


Here we have the injector connection next to the resistor box where I had previously tried to Vampire clamp to.

My Speed sensor is behind the cluster.. a Yellow/Red wire.

All wires were cut and soldered (calm down) with precision.

My ground is just connected to a bolt near the radio that I designated as my ground for all attachments..

[wyatta4]

So I changed the timing belt/water pump/valve cover gasket. It went well after I got the pulley bolt off..
Runs great now

But I have an idle problem.. its always been there.. I'm thinking maybe that it is the EGR valve..
So it is idling and sometimes it idles REALLY low.. then dies. Only occasionally though. and when its warming up it idles then the motor shutters just slightly.. not an injector, already checked that, and it isn't the prominent..

Any ideas? ill probably clean the EGR anyways.

On to the next topic. MPGuino.

I finally put about 430 miles on it with the MPGuino so I filled up and fixed the settings.. It works right I think but a couple of quirks I'd like to point out.. and suggestions or words of advise would be great.

RPM's are off. How do I change that to be right?

Instant mileage fluctuates from around 60mpg to 150mpg while driving down the freeway sporadically.. Is that normal?

Once I hit 70 MPH my speedometer on the MPGuino starts to freak out and go from 70+ to 68 to 69 back to 75. Its wierd.. I don't know if this is because of my VSS or what..

Current Mileage: On the way back from filling up, on the freeway, the current milage got clear up to 90 MPG.. is that accurate? cause that seems a couple 30 mpgs off haha.. or is that just how it is right after the fillup?


And does anyone know exactly how big the 89 HF tank is? No one online has a definite answer.. Ive read 10.4G then 9.9G then 11G.. So i set it at 9900(seemed most logic) which is 9.9 Gallons, correct?

[myrefugeisintheLord]

I wish I could help you on the mechanical parts, but I'm not knowledgeable enough yet, in those areas.

One thing I can help you with is the tank size. On CRXcommunity, they clearly state that the HF holds 10.6 Gallons. It's in a popular thread on the differences of the CRXs. Source I'm sure if that was incorrect, someone would have said something!
Keeping the gallons on the gauge lower is a safer choice though. I ended up doing that with RAVadoodle after running out of fuel with 0.7 gallons left according to the gauge. I don't top off, so it's never going to be totally full.

It was good to hear an update!

[Tippey764]

Did you try cleaning the iacv with brake/carb cleaner?

My 91 Integra is actually doing the same thing. I'm pretty sure it'd a dirty iacv though

That or you're low on coolant / have air in it since the iacv uses coolant to operate.

[wyatta4]

Originally Posted by Tippey764

Did you try cleaning the iacv with brake/carb cleaner?

My 91 Integra is actually doing the same thing. I'm pretty sure it'd a dirty iacv though

That or you're low on coolant / have air in it since the iacv uses coolant to operate.

thanks for the tip. I cleaned it and that wasn't the answer.. Didn't seem dirty really at all..

Coolant is up.

I am going to clean the EGR ports soon.. Those seem to have a huge affect.

Also considering an EGR delete plate. Any objections to deleting the EGR in my HF?

[War_Wagon]

Coolant temperature sensor? Just a guess, but they are cheap, and they can cause weird issues when they fail. If it doesn't do it when it's cold, but does do it when it's warm, maybe the computer is getting weird signals and getting confused?

[wyatta4]

Originally Posted by War_Wagon

Coolant temperature sensor? Just a guess, but they are cheap, and they can cause weird issues when they fail. If it doesn't do it when it's cold, but does do it when it's warm, maybe the computer is getting weird signals and getting confused?

I will check that out..


On a happier note... Took a 270 Mile trip and she made her personal best at 61 MPG

61 MPG!

[wyatta4]

It kept getting hot though... I need to cut a few holes in my grill block..

[MetroMPG]

61 MPG - congrats! What kind of route / driving style?

[wyatta4]

Originally Posted by MetroMPG

61 MPG - congrats! What kind of route / driving style?

One large mountain pass, Car will only do 55 going up it... hahaha
The rest has hills off and on.. mostly on..