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Discussion Starter #1 (Edited)
Here’s the low down of my situation. I had my 4 wire o2 fail me at one point, the car was running so rich you could see the gas coming out in liquid form from the tail pipe. And the car ran terribly. Other times it would run so lean you couldn't even drive the car till the check light came on. So I bought a new 4 wire and installed soldered all the connections and it worked great. The a/f gauge lights bounced back and forth. And it was always stoich. Now the next day I come out ready to drive and the a/f gauge shows nothing and the car is running lean again. I take everything apart and check the connections for the o2. Hook it back up and it works great again. The same crap happens the next day again. I have went through 10 bucks in gas in 2 days because this crap. I haven’t been driving it because of the gas prices, I can't blow all that fuel in 2 days at 3+ dollars a gallon. Any ideas why the o2 works and then doesn’t over and over. It’s heating, I took it out and turned the ignition on and it got warm. I'm about fed up with the whole turbo thing. I enjoy it, but if the car only runs right 30% of the time its no fun. Or is it just time to invest in a chipped obd1 setup? Any ideas, I am at wits end and don't have the time or money to put into it right now, I just want to enjoy my boosted car like I did 2 years ago, when it ran perfectly all the time. Now like crap. Any ideas would be appreciated.

:wzbigcry:
 

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What are you using for fuel management....fmu or afc?
A chipped obd1 setup is certainly a much better route for many reasons. Of course ideally it would be accompanied by a hearty tune :)
If the wiring and connections for the o2 are all good I'm not sure what the problem could be. You haven't used additives, etc. that aren't o2 sensor safe have you?
Any exhaust leaks before the sensor?
 

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Discussion Starter #3
I just have a fuel pressure riser on the fuel return and a walbro pump. This is all I have had for the entire time. No I don't use any additives and no exaust leaks from what I can tell. I didn't want to spend the money on computer to run this turbo setup, but its kinda heading that way, I just don't understand how it ran fine then one day not. Also I don't have access to a chip burner or anything if I didn't get the obd1 setup. I won't have a problem modding the ecu but then I need a harness uhh, pain in the booooty.
 

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Get a fuel pressure gauge, if your fuel tuning is entirely rising rate FPR based this is probably a problem regarding that.

Computer controlled fuel management is obviously far more accurate, and generally easier to diagnose, but it does cost some cash.

If you want to keep the cash level down, and don't mind doing a good chunk of custom wiring work (took me two or three hours, not THAT bad, just soldering) check out Megasquirt, it's a standalone ECU, totally custom, it can run just about any car out there, but is plug and play on no cars at all.

But yeah, fuel pressure is the place to start.
After that, check out the injectors, one may be stuck open or closed randomly.
My bet is that the RRFPR is failing.
 

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Discussion Starter #5
if it was stuck all the way open at idle I should still have the a/f reading normal wouldn't It? Do you have a link to the megasquirt thing.
 

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If the RRFPR was stuck open at idle things should be normal, and under boost very lean.
If the RRFPR is stuck partially closed and/or operating at a different ratio (like if the spring broke, it'd end up being 20:1 or something) it'd run way rich at idle, and even richer under boost.

Either way, the first thing for a fuel system problem is to make sure the basic system is working right.

I don't think gauges cost too much, and the 10mm bolt on the fuel filter is a wonderful place to plumb one.

www.megasquirt.info is the main site, www.msefi.com is the forum, you'd be after Megasquirt N Spark - Extra, or Megasquirt2, those do both ignition and fuel, where the origional software is just fuel.
The MSnS-E code uses the standard MS board, and is just a different set of programming you upload via the serial port on the box.
 

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Discussion Starter #7
I will look in to the rrfpr thing, I have been looking at the ms for a while today looks very promissing, ecept the install to the car, was that very difficult to get working I saw some of your posts with issues. Does the car run good or better. Is there a inital code you upload to make the car run like a basemap? Or does it just calculate it with the info you specify. Do you have any pics of the install? How much did the final setup cost you?
 

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I had problems with mine, mainly because i didn't buy the new (v3) board that can read the TDC sensor directly, i did get it to work though.

It ran about the same, really, the stock ecu is well tuned for stock.

The timing map you have to make yourself, i dug up an integra map and put the values off it into megasquirt for a basemap, for fuel it will generate one for you based on engine displacement/rpm/hp/torque, and it's generally quite accurate for n/a.

It is HIGHLY adviced that you get a basic wideband sensor, the $200 in-line controller ones work well, and megasquirt can read them directly.


To wire it in i bought a prelude ecu ($10) and hacked the guts out of it, then stuck the megasquirt into the case, and made a obd0-MS conversion harness using the connectors, it took a while, but wasn't hard.


Generally speaking, it goes on with some, but not much, difficulty. Mine was rather of an odd case, there is another guy on the msefi boards with an integra (same damn sensors), and his went right on no problem.
 

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Discussion Starter #9 (Edited)
http://www.glensgarage.com/catalog/product_info.php?cPath=1&products_id=30
Would this be the one I should get If I bought it? Or is there another kit you might recomend. Also one more question, I'm not that electionics savey, I am convident I could assymble it just don't no all the terms and how to test everything if theres a problem. or would it be pretty straght forward? Also would you recomend the simulator and relay kits? Maybe you could help lead me to what I need to get.
 

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Thats the correct kit.

I didn't assemble mine, i had a friend do it, as my soldering is worse then terrible, but he said it was pretty easy stuff, good directions and such.

The stimulator is very useful for testing if you run into issues, i didn't buy it, but it probably would have saved me some head scratching time :p

The relay board you shouldn't need, all the relay requiring circuits on your car already have relays on them, at least as far as i could tell.


He's probably right about your injectors, as far as testing goes, i'm not exactly sure really, the only way to do it that i know of is to take 'em out and hook them to a fuel source, then trigger them and see if they work.

DSM 450's will of course require some sort of electronics to tune, the RRFPR can't do it.
 

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Sorry to hear the old setup is breaking down.:-(

Looks like you might to just have to come out the pocket and get Chipped ECU or the Megasquirt ECU.

Either way, it seems like the stock injectors are tired and they want to give up.

But like at the bright side, you were able to last this long on a simple setup and fairly reliably. You proved it can be done for a certain amount of time.

And with the chipped ECU or MS with the 450cc's injectors, you will run even longer and more reliably.:)
 

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you can also take your injectors out and have them flow tested. By the way you might want to look into a local factory ecu tuner in your area, and then all you would have to do is convert to obd1 get a chipped ecu and go get it tuned. Done.
 

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hondaprelude88 said:
How would I test to see if there properly working still, or is it dsm 450 time?
Yeah, flow testing is your best bet. The problem is it costs $$$ to get them tested. You could use them money on buy 450's getting them balance and tested. The process would cost the same money.
 

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I also want to add that unless it's a high dollar air fuel gauge then it's probably just about worthless and good for nothing but show. Don't believe much of what it reads!
 

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Discussion Starter #17
I will look into testing the injectors, does anyone know what type of shop does this? I will continue to look into the megasquirt thing. It seems like the best bang for my buck, I could even ditch the btm and make my money back + some. Bob is there any way I could get you to send me the config you make for you car with megatune if thats what your using I just was curious what numbers I would need to punch it to get an idea of what I would be in for. Also what type of electrical mods are we talkin for the dsm 450's I thought it was just modding the seal so they fit. I know the a/f gauge isn't the best but I know when theres nothing on there that somethings not right. lol
 

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yeah, sell that btm... my thoughts when i went for my odb1 setup were. the price of a rrfpr, and the cost of a btm... compared with the costs of setting up the obd1. maybe it would have been a bit cheaper to go with the rrfpr and btm, but it really wasn't the best option by far, and the price difference was really nothing too much.
 

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What you would do for starting map is generate one based on the stock numbers ([email protected], [email protected]?ish?), then add rows for boost, and put numbers in them that you know will run very rich.
That gives you a safe base map that you can work on, leaning things out till they are about right.

Timing wise you pretty much just have to guess, or steal a map out of someones chrome/uberdata/whatever setup and copy it peice by peice into megasquirt.
 

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Discussion Starter #20
How do you add rows for boost, or do you mean richin the rows that are under boost? Is there anything that will just allow it to add fuel based on the amount of boost? I couldn't find anything on timing, I have been just playing with it for a while It looks like a decent program. Now I just need to think about spending the money and time to get one.
 
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