The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support STM Tuned
Please Support Rix Racing

Codes P0135/P0325/P0510 at the same time?

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Tsmith

10+ Year Contributor
223
1
Jan 23, 2010
Colo Springs, Colorado
97 Eclipse GSX, Auto trans, 16g, VRSF FMIC, 3 inch turbo back exhaust blah, blah, blah.......

Ok so while on the highway two days ago I noticed I was getting an exhaust leak. I was also losing both un-boosted power and boosted PSI. I thought maybe the exhaust leak was pre- turbo and causing the car to not spool properly and maybe a sensor to act up. I have felt my car act this way before and the issue was a plugged Cat. When I found the plugged cat I cleared all the honeycomb out of it so its basically empty now.

Today I went to work on the exhaust leak and found a leak between the manifold and turbo, and also between O2 housing and downpipe. I tightened the bolts on the manifold/turbo leak and it went away immediately. I pulled the downpipe down far enough to grab the old gasket and throw some high temp gasket maker on it and bolted it all back up. Started the car and exhaust leaks were much much better.

I decided to do a compression test because I have never done one on this motor. Everything there was fine. I only include this information so you can have an idea of everything I did today.

When I started my car up again I noticed the CEL on and looked at my gauges. Everything was fine except my narrow band O2 (which is normally stoich on idle and pig rich on full throttle) was as far lean as it can be. While driving home (since I had to get home anyways) I had to be almost 60% throttle or better for it to start to pick up. I also had a bunch of stuttering while driving. Also the transmission seemed to be having a hard time finding the right gear to be in. Decided to pull into Advance Auto to get the codes pulled.

Here's what I got:

P0135 Heated Oxygen Sensor Heater circuit Bank 1 Sensor
P0325 Knock Sensor 1 circuit
P0510 Closed Throttle Position Switch

So I can assume the O2 sensor went bad and maybe while pulling the down pipe I caught the wiring, no big deal. I also see that whoever wired the A/F into the car did so by using a butt connector on the engine side of the O2 harness and some of the wiring is exposed. There is also a wire (same spot) next to the one he spliced that is missing some insulation and could have shorted out on the transmission (maybe causing the O2 to short out).

Does any of this make better sense to anyone else than it does to me?

Why the other two codes if it is just an O2 sensor?

Am I on the right track with replacing the O2 sensor and repairing the messy wiring?

Is there any other damage that could have happened from the possible shorted wires?

Can the codes I have now have anything to do with the Transmission problem?

Any suggestions in advance for anything else I should check/replace from the two codes I have before I try an O2 sensor?

Thanks for your time!
 
There are small heaters in the o2 censors and when they go out causes problems on the exhaust side so deffently replace the o2 sensors. the knock sensor they get old and crystalize and they just break off giving you a false reading which also will make the car run bad. the throttle sensor also will effect it as to why you were having to give it excessive throttle. combined correct me if im wrong it seems these conditions would probally be your problem not the transmition i would assume. it was probally confused in what gear you wanted to be in due to using so much throttle so i assume your rpms where probally not normal either so i would fix that stuff first then dianose the tranny.
 
I agree with everything you said, I guess I am asking more if its possible that the issue is ONLY the o2 sensor causing everything else to happen, or do I need to plan on replacing o2, knock and tps sensors all at the same time?
 
P0510 Closed Throttle Position Switch can be a bad throttle position sensor which would affect how the trans shifts.

I agree with everything you said, I guess I am asking more if its possible that the issue is ONLY the o2 sensor causing everything else to happen, or do I need to plan on replacing o2, knock and tps sensors all at the same time?

You could start with o2 sensor but your probably going to have to test all 3 and replace if necessary , look at the knock sensor and see if it looks like black stuff is leaking from it, you can also search on here for the procedure to test the TPS.
 
Well personally this is what i would do fix the o2 sensor first then have codes read again should either take them all off or you will still get some other codes eliminate one part at a time. Its always posible the o2 effecting the air mixture making it run rich. hope that helps just what i would personally would do
 
In my mind there is no way all three sensors just went bad at the same time!
 
well it makes sense why those three are flashing codes they all work together to insure your geting the proper air and fuel mixture for your set up. so if one goes out then it effects hole system and makes your car run like crap
 
Sounds good all, thanks for replies! I will fix the o2 and go from there.
 
I would check the TPS first.

If it is reading closed while you driving and have the throttle opened the ecu would have a hard time figuring out why the MAF is reading so much air with a closed throttle. The ECU could have leaned your injectors out. Lean conditions can cause knock and could also make it think the O2 is reading wrong.
 
In my mind there is no way all three sensors just went bad at the same time!

They may not have all gone bad at the same time. Sometimes codes can be stored and not trigger a check engine light. The o2 sensor code definitely will trip a light but the knock sensor may not depending on frequency of failing the test. I would replace all 3 sensors as they don't really operate on the same circuit and are common code failures.
 
Here's what I got:

P0135 Heated Oxygen Sensor Heater circuit Bank 1 Sensor
P0325 Knock Sensor 1 circuit
P0510 Closed Throttle Position Switch

Hey bro, I just scanned my car tonight at school and I got the P0510 code. Did you ever figure out why yours threw that code (before you sold it)? I'm thinking I'm gonna need to replace the TPS, but need to research more.
 
I replaced my o2 and cleared the codes and they never came back! Sorry as I am sure that doesn't help you.
 
It still helps. The other code I had with it is P0170: Fuel Trim Bank 1. That itself indicates the o2. After installing the exhaust on Saturday, I could tell both o2s need replacement, but I'm wanting to get a Wideband soon, so I don't knowif I'll replace the upstream sensor yet.
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top