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Hello everyone my name is Matt. I noticed that my 1993 honda del sol si was not getting to operating temp so i was going to change the thermostat and found that I didn't even have an old thermostat. I went ahead and replaced it and my car gets to operating temp now. My problem is it runs fine when its cold or warm. but when its warm and at idle the RPMs fluctuate from 1200 to 800 over and over. plus i'm getting a check engine light for 41, 43. People say it could be o2 but it was replaced 3 months ago. Thanks in advance for any help.
Make sure you have properly bled the coolant of air with the heat selector set to hot.
Clean the iacv and fitv plus thread the plunger back into the fitv as they tend to loosen over time allowing excess air passed the tb when it's warm. Check the vacuum lines for holes and pcv for proper operation
Double check the the wiring to the o2 sensor and replace again if necessary.there are tests for the o2
41 is your primary O2 sensor. 43 is a generic fuel system code. The 43 error could cause bad readings throwing the 41, or it could have fried your new O2 sensor, causing the 41. You need to buy/borrow/rent a fuel pressure testing gauge. Once you have one, do three tests.
First, attach the fuel pressure gauge. Once you've done that, turn the key to ON(II). Don't try to start the car. With the key turned to ON(II), what does the gauge read? Now disconnect the bottom vacuum line from your fuel pressure regulator. It's a small, metal cylinder thing sitting on your fuel rail. After detaching the vacuum line, what does your gauge read? Reconnect the vacuum line. Does the gauge return to the previous value, stay at the disconnected value, or something in between?
As for the RPM fluctuation, you just need to do a better job of bleeding your coolant. Put the front of the car on jack stands (or park it on a hill), remove the radiator cap, and start the car. Let it run for three fan cycles. Should take ~10-15 minutes from a cold start.
Thanks for the advice. I'll try what you both said. I have a warranty on the o2 sensor so I plan on replacing it tomorrow. I did bleed the coolant once but i did not have it on a hill at the time so i will do that tomorrow as well. Its weird i drove my car all summer when it was warm and had no problems. Now that its cold the check engine came on I started burning fuel. I wasn't loosing any oil or coolant and black all over my rear bumper from my exhaust. My car was always cold from the thermostat being gone it never came above the bottom mark on the guage. I assume because i replaced the thermostat and my car gets to operating temp on the gauge and no black on my bumper now. hmm
The black on your rear bumper is caused by your car over-riching itself. Basically, it's shoving too much fuel in there, wasting gas, and leaving **** all over your bumper (and your O2 sensor, killing it). Do the fuel pressure tests, and we can work from there.
The black on your rear bumper is caused by your car over-riching itself. Basically, it's shoving too much fuel in there, wasting gas, and leaving **** all over your bumper (and your O2 sensor, killing it). Do the fuel pressure tests, and we can work from there.
This
Then proceed to pressure test the cooling system to verify headset is sealing
The black on your rear bumper is caused by your car over-riching itself. Basically, it's shoving too much fuel in there, wasting gas, and leaving **** all over your bumper (and your O2 sensor, killing it). Do the fuel pressure tests, and we can work from there.
Okay do you have any advice on where to get one. Harbor freight has on for $20 but most of their stuff is 1 time use or junk and Autozone wants $150 to borrow it.
I was about to go rent a fuel pressure gauge and i noticed i didn't have any of my evap and my oil separator wasn't hooked up it was plugged with no pcv valve. I went to the local salvage yard and got all of it. when i started hooking it all back up I noticed i didn't have a plug too hook up my purge control valve.
then i found something that was just hanging where the plug should be for the purge control valve. what is it? is it just an old broken one? could any of this be a problem too. Could anyone tell me what the random line from my firewall is also?
After thinking a bit....your intake air sensor laying out is causing a vacuum leak. It goes in the intske manifold.
The solenoid mounts to the top right of the manifold and connects to the canister and small nipple on intake manifold. The bottom connection to the intake
I checked their is no spot on the manifold for it. I think the manifolds off a d16y8. i check near the plug for the sensor and their isnt a plug for my purge control solenoid..
I checked their is no spot on the manifold for it. I think the manifolds off a d16y8. i check near the plug for the sensor and their isnt a plug for my purge control solenoid..
I think the y8 had the air temp sensor in the intake arm. As for the purge either leave it hangin or tee of a vacuum location
That manifold...does it have the iacv on the rear of the manifold or under the tb?
My bleeder screw wasn't opening so i had to take it off and clean it today.
I'm gonna bleed it tomorrow morning. One main thing is the iat sensor was plugged in and hanging but i have no place to plug in my purge solenoid. could it be cut? could i run a new one and auto zone didn't have an 02 in stock so they are getting it tomorrow and im replacing it. one last thing is my charcoal canister one of the lines on top should lead to the throttle body and their is no spot on my throttle body and line is just chilling their.
The evap system is not that important at this point.
As for the wires, either ron can post a diagram or you can wait for me take take pictures of mine for wire color and location.
The solenoid needs a vacuum source, the top of the canister needs a pre throttle plate location, ie no vacuum.
The iat, extend wires and locate to the intake arm as necessary
Also blindly throwing an o2 sensor at something is not diagnosing.
I'd appriciate if you could get pictures when you have a second.
Since it needs a pre throttle plate location should i get a different throttle body eventually with a spot to plug the hose in.
I'm going to extend it tomorrow if its important to have.
The only reason i'm replacing the 02 instead of reading it is i have it under warranty and i was running rich before and i'm pretty sure its the code im throwing.
I really appreciate your help
i have a 1993 honda del sol si. d16z6. I noticed all my evap was gone so I decided to get it all and replace it. When i went to plug in my purge cut solenoid valve I looked behind my intake manifold and only found 1 connector that would work but it was pluged into my iat sensor. am i supposed to have another connector?
12-24-2014, 06:19 PM
93 d16z6 rough idle and check engine light on
