When I got the ECU in the mail today, I temporarily plugged it into the cable and drove from my apartment to my parents' house to install it. I noticed the gains right away. There was no ECU light. WHen I got home, I proceeded to remove the old ECU and finish installing the new one. It was a pain to install. Took me well over 4 hours to figure out how to remove the damn screws even with Cheston's instructions. The car ran fine after that the install as I took a spin around the block. I pullled up to my driveway and see the ECU light. I check the codes and they all deal with the EVAP solenoid, EVAP sensor, and PCV. I figure maybe it was just an error on the ECU settling in. I reset the codes and start the car. The car sounds like if it's about to die, but still remians on. The RPM is reading near 0 though. I open the hood and hear a ticking noise by the PCV. What's going on all of a sudden? The car was fine just a second ago with both ECUs. Please help.

 

The ECU light went away while I drove back to my apartment. When I parked, I turned off the car and started it back up again to see whether the problem was still there. Sure enough, the ECU light came on and the RPM was near zero. Even with the ECU light gone temporarily, the RPM problem was still there during my drive back, but the car was quicker off the line dut to the GeForce ECU. I'm thinking of changing the PCV valve tomorrow. Does anyone know what's going on or what I should do? I'm in medical school right now and don't have that much time to waste. Thanks

 

same thing happened 2 me yesterday when i put my techno ecu in, but i got different codes, i diconnected the battery for 15min and reset ecu and all went back to normal, i dont know why though, check your MAF also..

 

One time i was resetting my firends ECU, I did not turn the screw all the way. I turned on car and it was idleing at 200 RPM!! So i reset his ecu the proper way and his codes have not come back and it runs great.

Reset your ecu and post your codes.

 

Ike, that's strange. I didn't have that problem when I had the Techno ECU. No codes or anything other problems whatsoever. I didn't even have to reset the ECU or disconnected the battery. Hope you get it fix.

 

If your ECU worked without any errors, the first time that you plugged it in, the only thing that I can think of is that the connector might have dislodged itself a bit when you were actually installing it. Unplug the connector and plug it back in and see what happens.

I think you need to disconnect your battery before you do any of this though... did you do that when you were unplugging and plugging the ECU in and out?

 

That may be it. I didn't disconnect the battery when I I was switching the plugs. I tried what Maximum96 and kevlo911 did but the ECU light was still there. I'll try disconnecting the battery and switching them now. Thanks for all your help guys. I'll report back.

 

I disconnected the battery when switching between the two, but the light still shows up only on the Technosquare ECU not my stock one. It even blinks when I'm in park.

I get these codes

0801: Vacuum cut balve bypass valve
0803: Absolute Pressure Sensor
0807: EVAP Canister purge control valve/soenoid valve circuit

 

thats weird. I had just plugged my G-Force ECU in and I got no codes at all. I drove around with it and went home to take my stock one out and finish installing the G-Force. I disconnected the G-Force and finally got it installed and put the connector back on and got Error code 1008 which is for the EVAP canister purge volume control valve. We unplugged the ECU and plugged it back in and the light was still there. It's been a little too cold for me to figure out what exactly it is. Also couldn't find fuse 58 which it says to check. I even tried resetting the ECU and as soon as I started the car up the check engine light came on.

 

That's exactly how mine started! It was fine in the beginning and started actng up. I also got that code. I reset the ECU several times and the light disappeared for the duration oy my errands. However, it came back on after the car sat for like three hours in the lot. The engine is now more audbile after startup but the RPM still deeps to like 200 at idle while at a stop. The car doesn't struggle to accelerate or anything like it. I wonder what the solution could be. These problems don't show up with my old ECU.

 

I may be way off here, but it kind of sounds like your ECU is in diagnostic mode. check the screw, you might have forgotten to turn it back the correct way (counter-clockwise? I forget) after the last time you pulled your codes.

 

Yes, mchne is correct. That is exactly what it sounds like. Try messing with teh screw, it might be in the wrong position.
Contact G-Force/Technosquare and see what they say.


0801
Diagnostic Trouble Code 0801 points to a problem with the Vacuum Cut Valve Bypass Valve. The malfunction is detected when an improper voltage signal is sent to the Engine Control Module through the VCVBV. The possible causes of this problem include a defect with the wiring or electrical connector, or with the valve itself. The VCVBV is located under the car, near the rear left tire. It is near the Evaporative Emission Canister but not mounted directly on it.

The VCVBV is a solenoid-controlled air valve. You may remove it from the vehicle and perform a bench test. There are two air hose nipples on the valve. Fasten a length of clean rubber vacuum tubing to either nipple. Gently blow through the hose. The valve should be closed and it should be difficult or impossible to send air through the valve. Now use a pair of fused test leads to provide 12 volts to the electric connector. The polarity doesn't matter. With the VCVBV solenoid energized the valve should be open and it should be easy to send air through the valve.



0807
Diagnostic Trouble Code 0807 does not appear in the '99 Maxima factory service manual, and that is my principal information source. I'll tell what I know about the '99 Maxima EVAP Canister Purge Volume Control Solenoid Valve. This information may or may not apply to your Maxima.

The Evaporative Emission (EVAP) Canister Purge Volume Control Solenoid Valve uses an on/off duty cycle to control the flow of fuel vapor from the EVAP canister. Diagnostic Trouble Code 1008 is set when the Engine Control Module (the computer) detects an improper signal through the valve. The problem is likely to be in the electrical wiring, harness, or the valve itself.

Check fuse #58 (10 amps) and replace if necessary.

The CPVCSV is easy to see and reach. It is located in the engine compartment, mounted to the top of the upper intake manifold. Notice the Vehicle Serial number stamped into the firewall. Put your finger on the third-from-last number. Move your finger three inches toward the radiator. That's the CPVCSV. It has one two-wire electrical connector and two vacuum hoses.

You may test the valve. This test procedure is performed with the engine off. Remove the electrical connector and both vacuum hoses. Fasten a length of clean rubber vacuum tubing to either nipple. Gently blow through the hose. The valve should be closed and it should be difficult or impossible to send air through the valve. Now use a pair of fused test leads to provide 12 volts to the electric terminals. The polarity doesn't matter. With the solenoid energized the valve should be open and it should be easy to send air through the valve.


http://forums.maxima.org/showthread.php?t=265311

These might help.

 

This is not sounding good. i just ordered my TEchno ecu. Can anyone PLEASE tell me how to take out my 97 ecu and put in the techno ecu. From what i have read it seems like athlon omega had both ecu's plugged in at one time? I am having a hard time understanding this thread. Can someone please explain to me how to EXACTLY swap ECU's and and if i should disconnect the battery etc ..

Thanks guys !

 

I played around with the screw several more times. THe ECU light goes away temporarily but comes on soon after. This morning, it was blinking while I was driving. I came back and reset it like 3 more times and got the same problem. I'm thinking of checking fuse #558, but I don't know where it is. Does anyone?

96white, I only had one ECU connected at a time. What I meant was that I one ECU was installed in its position on the floor behind the dash. When I wanted to switch to the old ECU I took out, I would connected the cable temporarily to stock ECU. It would hang out and lie on the floor of the passenger side.

 

yea man, my ecu was throwing o2 sensor, and knock sensor, but I reset ecu and it was at 200 rpm when start so i reset again and its fine and never came back..

 

This has a been a problem with G-Force ECU (throwing odd codes, poor running). I remember when the ECUs first dame out and quite a few people had to send them back. This is not to say JWT doesn't have thier problems also, but JWT does know that some early model 1995 ECUs don't accept thier programming. I have a feeling there's something with Technosquare's program that has conflicts with certain model ECUs also.


Dave

 

what do you mean early 95 models? I just ordered a" after 11/95 " on car-parts.com ecu which i believe was for a 04-96 model. ?????

 

Early would mean 1994. The 1995s came out in August of 1994 so the ECUs have 1994 build dates. A "after 11/95" will work fine. That's what I'm running in my Maxima.


Dave

 

so you dont have any check engine lights at all?

 

**so you dont have any check engine lights at all and never did ?? ***

 

none.


Dave

 

I got the ecu from 96sleeper, it's a 96 auto ecu. It should work fine. None of these codes show up on my old ecu when I plugged that in to check. However, does anyone know where the #58 fuse is? I figure that's the easiest thing to change. The post that you gave kevlo911 was helpful, but the drawing of the fuse was separate from the rest of the engine. The placement was alos different since it was of a 97-99 maxima.

 

Bump

Could the fact that my car is a 95 auto using this 96 auto Technosquare ECU be an issue? I didn't think it would since both ECUs are auto and both don't have a top speed limiter.

 

Did you get the same model ecu as your vehicle? ie SE to SE ecu?

that could be why


dan

 

No, I highly doubt that is the case.

Also, ECUs are not trim specific (GXE, GLE, SE).

I'm sure that the ECU is fine, if it worked the first time. I bet it is a loose connection (tighten that 10mm bolt again) or like I said earlier, if you unplugged the Technosquare ECU without unplugging the battery, that MIGHT have done some damage.

Call Technosquare and see what they say.

 

JWT and Techno both ask you get an ecu that matching you model. Everyone on the forums says the same. I would check that.

 

Hmm... before I got my JWT ECU, I called them and they said that even an auto gen 4 ECU would work for them to program for my 5-spd (don't ask me how). But I ended up getting them an ECU from the same production run as my Maxima and sent them that one, keeping my stock one in the car).

But if all else fails, maybe the ECU date does matter.

 

I spoke to the guys at Technosquare. They said that the ECU may have been dmaged during shipping. I tried the whole setupover according to what the guy told me. I still get a ECU light with the modded ECU and an RPM of 300 at park compared to that of 800 on the stock ECU. He said they would charge $150 to look at it. Considering that I paid $400 for it and I'm not the original owner, there is not much that they can do for me.

 

Damn... that really sucks man. Sorry to hear that. But you could also think about making the best of the situation... maybe save up and send it back to Technosquare to have them look into it. It is an expensive ECU to just throw to waste.

BUT I still have my doubts... why did it work perfectly the first time and then not work the second time?? What changed in between?

 

Ike, want me to take a look at it for you? We could plug it into my car and see if we see the same codes. You got to come back here though, Baton Rouge is too far for me to drive.