Need Help urgently.

[SexySilverST-X]

Hey friends. I had my D40 engine washed yesterday. And when I woke up this morning and started it it gave me a very rough idle and then eventually shutdown after about 10secs. I also realized my engine light came on. I used my wireless OBDII blue tooth to connect to my app TORQUE on my phone. Check for fault codes and only one code came up which is POWERTRAIN P1275....... I checked the MAF sensor before the air filter, used contact cleaner and a can of air spray to remove, if any, moisture. Tried to start again and still same problem..... I think the she's in LIMP MODE. How do I reset the ECU to clear limp mode ????

 

[3ltflogga]

Google gives you options, some of which look expensive. Perhaps a bit of WD40....


P1275 - Nissan
Type Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled
Description
Air fuel (AF) ratio sensor 1 - response time
Cause
HO2S, AF sensor, fuel pressure, injectors, intake air leak, exhaust leak, MAF sensor

 

[SexySilverST-X]

Ok, but those things still don't male any sense to me. Is there something I need to change? I thought all I had to do was reset ecu or erase code.......I'm still stuck

 

[happy john]

A simple ecu reset is to disconnect the battery and place a load eg foot on the brake re connect the battery. How much pressure did you use cleaning that maf sensor with compressed air?, I only use the contact cleaner the solvent evaporates.

 

[kernels]

It has to be water in a connector somewhere. Start from one side and start unplugging and blowing out with compressed air.

 

[Old.Tony]

The D40 manual (page 1252 of EC.PDF) says it's possibly a fuel pump harness issue and that could well be - especially after cleaning the engine bay. Pressurised water in connectors can push debris between the contacts. Nissan seem to use P1275 in the YD engine for "fuel pump over pressure" and they suggest that it may be a harness issue.

 

[SexySilverST-X]

Old.Tony , after a six pack and lots of troubleshooting I got the reason for the problem. Water actually got into tuning box that I had connected to my fuel rail. So apparently it sent a wrong reading to the brain....... so I took out the chip and connected the original harness jack into the fuel rail. Started as normal, but was still in Limp mode.... so sent it back to the company, and from what I know it was just a reset or cleared the fault and it worked properly............... The only thing is, I don't want to take the chance of connecting back the tuning box, as it may be screwed!!!........ so I'm missing that little extra performance that the tuning box was giving me.......but don't know what chip to buy now.

 

[happy john]

I thought chip "tuning box" immediately but as you didn't mention one ???. Those things aren't waterproof nor are the connectors.

 

[SexySilverST-X]

I thought chip "tuning box" immediately but as you didn't mention one ???. Those things aren't waterproof nor are the connectors.

So john, u think the tuning box is screwed? How can I tell without hooking it back up and getting a engine light and limp mode?

 

[happy john]

It's only a thought it may be screwed some circuitry can dry out and recover, you have to eliminate all the possible problems start with the chip and connectors. Remove the plug on the rail sensor and put it back on standard tune, engine lights?, that's a start you may do better later someone will have a better idea than me all the best.
John

 

[Old.Tony]

If there's no warranty on the tuning chip (and after giving it a bath, I expect not!) you could open it up and check for corrosion, cold solder joints, look at the external connectors which may have some oxidisation on them (especially if they're silvery connectors, gold ones are usually more resistant to oxidisation).

Without taking it back to the manufacturer so that they can test it, the only way you have of knowing if it's functional or not is to try it again as John suggests.