'86 crx si check engine light

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windraver

New Member
'86 crx si check engine light & alignment

just rebuilt my engine, changed the O2 sensor, spark plugs, gaskets, belts, etc

the pgm-fi light is on... check engine light.. same thing

anyways, the ECU light 1 is on... so its either my O2 sensors, or mis-fire.

I didn't change my spark plug wires, could that be a problem? a listed item was also insufficient fuel? its either one of those or else its my ECU.. -.-

any ideas?

Note:
Engines is EW4
Fuel injected

- oh yea, i was always wondering.. premium gas or regular?

edit:
could it be possible that my fuel pump is weak or my fuel filter is clogged and resulting in insufficient fuel?
the check engine light doesn't come on until a good length after i've driven it about.... 10 minutes. the car runs great to be honest, i just hope to figure out why theres an error light
 
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I'd probably go ahead and change the wires too. It won't hurt and they're not that expensive. And I don't see any reason why you'd need to run premium gas on a motor like that.

A clogged fuel filter is a possibility. Those aren't horribly expensive, so I'd probably go ahead and change that too.
 
Perhaps the O2 coupler is not contacting? Code is ilso for a short/open circuit in oxygen sensor....
 
checked the O2 again, its got continuity, checked the readings also.. seemed pretty good... found the wire going from the ecu and tapped another point after the connector... so its connected

checked to see if it was short anywhere and there was no continuity to ground so O2 was out of the picture...

couldn't have been the fuel filter since my car ran pretty well... the engine light just went on...

so last two things were misfire or messed up ECU

spark plugs were replaced during the rebuild... but not the cables
and so it turns out that the spark plug cables were really... lose... kinda stupid lose.. but it worked.. which is odd...... made the connection tighter... but never got to fully test it...

since the crx got in an accident.. someone hit my rear driver quarter panel.. kinda bent my rear axle too... makes driving it at 30mph scary... -.-....

so i'm guessing i'm replacing the rear axle now... and anything else thats bent.... probably pulling out the quarter panel and body filling the rest... just.. disappointing... since i just finished rebuilding the engine too -.-

how is alignment on a crx done? my toe isn't insane but it would be a nice thing to adjust....

i think i'm gonna use my axle replacement as an excuse to do the integ brake swap... i found some sources but anyone know any really good guides to this out there? and is there anything i should know about the rear axles on the crx? ... like things i should not do?
 
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Changing the plugs is a good move, and the fuel filter. These should be part of your routine anyway.

But the CEL you're getting is likely an 02 sensor. If it was misfiring, you could hear and feel that.

O2 sensors RARELY, if ever, "go bad". They are solid state, and easy to test. Here is how I test mine:

Take it out and bring it to the workbench.
Grab your torch and get the end of it hot. Hook up your multimeter to the wires and look for DC voltage. The voltage out should be between .01 and .15. If you use MAP it should be higher, but never over .9 volts.

Then check your wire from the O2 sensor to the ECU. Look for a short, or some sort of break.

The fuel filter is easy to do, it's on the firewall next to the heater core. Remember to be very careful with the crush washers (Crush washers in that size are expensive and hard to get)
 
checked the O2 again, its got continuity, checked the readings also.. seemed pretty good... found the wire going from the ecu and tapped another point after the connector... so its connected

checked to see if it was short anywhere and there was no continuity to ground so O2 was out of the picture...

couldn't have been the fuel filter since my car ran pretty well... the engine light just went on...

so last two things were misfire or messed up ECU

spark plugs were replaced during the rebuild... but not the cables
and so it turns out that the spark plug cables were really... lose... kinda stupid lose.. but it worked.. which is odd...... made the connection tighter... but never got to fully test it...

since the crx got in an accident.. someone hit my rear driver quarter panel.. kinda bent my rear axle too... makes driving it at 30mph scary... -.-....

so i'm guessing i'm replacing the rear axle now... and anything else thats bent.... probably pulling out the quarter panel and body filling the rest... just.. disappointing... since i just finished rebuilding the engine too -.-

how is alignment on a crx done? my toe isn't insane but it would be a nice thing to adjust....

i think i'm gonna use my axle replacement as an excuse to do the integ brake swap... i found some sources but anyone know any really good guides to this out there? and is there anything i should know about the rear axles on the crx? ... like things i should not do?


so did fixing the plug wires solve the CEL problem? as for the rear disk brakes, yea they look neat, but if i had to do it again i would stay with drums. aluminum IF you can find them. the cost : reward ratio is heavy on the cost side.

hijack: e-man, what front brakes are on the ULT? i did a MC swap on mine. maybe i can help.



scott
 
Car has 1G teg calipers and incorrect SS lines (I believe Bryan said he used 2G CRX lines). Booster is working fine although I haven't been able to ascertain whether its the original (Nissen Kogyo NM-180V). Brakes feel mushy which I hope can be helped via a larger MC.

Any insight is most appreciated Scott.
 
iirc, the 1g teg had a 7/8 mc. pretty sure it bolts in. the 2g prelude also had a 7/8 mc and think it bolts in too. the 3g prelude had a 15/16 mc. it most certainly did NOT bolt in. about an hour later with a dremel and hand file, and it barely fit. had to seal it with silicone.

the car came with a 13/16 mc so any of these would be an upgrade. i recommend one that bolts in. ss lines are next on my list. when you get around to it, ford hd brake fluid is a well kept secret. hope any of that helps....



scott
 
Car has 1G teg calipers and incorrect SS lines (I believe Bryan said he used 2G CRX lines). Booster is working fine although I haven't been able to ascertain whether its the original (Nissen Kogyo NM-180V). Brakes feel mushy which I hope can be helped via a larger MC.

Any insight is most appreciated Scott.


Sponginess isn't solved in the volume of the cylinder. In fact, under most hydraulic cases the larger cylinder will make it spongier. (But brake fluid / hydraulic fluid doesn't really follow this curve)

I never saw the real impact of increasing the capacity of the MC .
 
Interesting perspective Celerity.

It was my assumption that the larger bore of the Teg (7/8) versus the stock 13/16 would move the fluid more efficiently. A even larger bore (15/16) MC is available on the 85 Prelude carb edition that bolts in according to the masses on RPR.


I'm assuming that the fluid is way overdue for a change as well as the pads. This seems like the logical first step.

Next search will be on the virtues of the variety of street pads out there. Appreciate the advice on the brake fluid Scott.
 
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yeah, by removing the crud (IE, new fluid) and braiding the lines you can see a marked improvement.

Moving the larger amount of fluid through larger lines won't do anything on the end piston. If you replace the whole system, then yeah - larger lines and MC MAY be called for.

I would go into fluid dynamics about compression, but at this level its negligible.
 
i always operated under the assumption that the more fluid you can move toward the caliper piston(s), the more force will be exerted on the pad, rotor, etc. assuming that all other parts of the system are well sorted of course; pads, rotors, fluid, lines, booster, mc, tires...... i actually want to hear the rest of the story, celerity. share your wisdom, dude.




scott
 
Hydraulic fluid has a compression rate. Granted, it's MINISCULE and won't make a huge difference here.

But imagine taking two pistons: one at an inch diameter, the other.. say... 4 inches diameter

Now fill them both up 1/4 the way and bleed the cylinder.

The larger one has 4 times the fluid as the smaller one, but which can you push the plunger down further in ?

The effect that you want is to NOT be able to push the piston down far. So when the piston starts to push the fluid into the lines, it's pushing less fluid, faster. Were it a larger piston, it would push the same amount of fluid, but would also have that compression at the liquid in the cylinder itself.

Again, it's not noticable to most metering equipment - so that's not the point. The point of my argument is that this one mod will make no difference in the stopping attributes of the car, except to make it un-noticeably worse.

If you upgrade ALL of the braking components along with the MC, then yes - you have something. The best braking mod that you can get is super clean fluid and braided brake lines, as well as lots of hose anchors to take up the slack of the compressed fluid in the lines.
 
lost me at hose anchors.




scott


As lines compress, they become denser. Denser lines tend to straighten out, or otherwise lose shape. Any movement in those directions is a few inch-pounds away from the pads squeezing. Same philosophy behind braided lines (Which I believe in). The braiding stops the pressure from wanting to expand to the sides of the lines.

The best thing for hydraulic fluids are pipes. But you can't get a pipe to a suspended and moving wheel. Use as little brake line as you can.
 
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