[beetz12]

My car: 97 Nissan Sentra GXE
Mileage: 72k

I had a CEL on for a while indicating an EGR flow malfunction. Today as I was checking my EGR valve, I noticed that the vacuum hose that connects to the metal pipe had completely rotted through.

After replacing it, my car idled very rough, with tons of fumes kicking out the exhaust and when I give the gas a light tap, the engine dies quickly.

To all the Nissan Gurus out there, does this sound like a bad EGR valve, or something else entirely.

Some additional information:

At one point I cranked the engine with the top Air filter assembly off and the throttle body exposed. This was before I replaced the vacuum hose on the EGR valve, and during this time the engine was already idling rough. I sprayed some air intake cleaner into the throttle body which made the engine die.

I was able to restart the car, but the sputtering seemed to get worse. I didn't think anything of it at the time because I figured the rough idling was caused by the missing air filter assembly. But now I'm having second guesses. Could spraying air intake cleaner into the throttle body while the engine is running cause any harm?

I appreciate all feedback.

 

[IanH]

Humm....
I haven't done this so I am guessing that spraying the MAF wasn't a good idea.
Read up on cleaning the MAF and see if its salvageable.
If not a new MAF is in your future !!!

 

[beetz12]

IanH, you hit the nail right on the head. I took my car to autozone yesterday and the scan tool showed a MAF malfunction. Besides spraying down the TB and MAF with TB cleaner, I also accidentally got some PB blaster (penetrating oil) on the MAF wire.

I drove for 16 miles yesterday and my car consumed 2-3 gallons of gas. At first I just figured the engine was burning off carbon deposits I'd loosened with the PB cleaner, but now I realize the MAF is most likely the culprit.

I may have to replace the MAF wire too. The connection end is secured by tape to a larger pipe appears to be a bit technical. Is this a DIY job or should I take it to a Nissan dealer to make sure it is done right?

Thanks for advice

 

[IanH]

Well again I haven't had to mess with this but its just a wire, so I would think that if you repair it with crimp connectors it will be fine.
Its the MAF senor wire thats super sensitive inside the intake, (it runs very hot) and make sure the ground is good, older cars have reported problems with poor grounds.

 

[beetz12]

Thanks for the suggestions.

If I did damage the wires with penetrating oil, you're saying I can repair it with crimp connectors?

I did not touch the sensor wire inside the MAF besides using a light spray of TB cleaner. Can you explain the proper procedure for checking the ground on the MAF connector? I assume this will involve a multi-meter...?

 

[IanH]

Well you will have to determine if the spray inside the TB damaged the MAF, I suspect it did.
Carefully cut of the loom wrap around the area you suspect is bad. Inspect the individual wires.
just spraying an electrical wire with cleaner wont do much unless you dissolve the insulation, so look for cracks and shorts, you shouldn't have any broken wires, but check.
The older B13's had ground problems, my comment was just to check the ground. Yes you can use a multimeter, any inexpensive one will do. I dont have a value for you, you could try the FSM or I could measure mine.

 

[IanH]

BTW if you don't have the FSM and phatg20 is down again I have one that's already on a site that you can download. If you want it let me know and I will PM a link.

 

[beetz12]

The MAF wires were accidentally sprayed with PB blaster which is a penetrating oil... although I wish it were a cleaner. Don't know if it will dissolve the wires but it's a possibility.

I've been finding mixed information online regarding the use of TB cleaner on the MAF. Some claim it does no harm, while others say it will damage the sensor. At this point I'm thinking the spray likely did damage the MAF.

Today I purchased a replacement MAF sensor and wire from ebay and hopefully should receive it soon. I'll post back with updates. If you can pm a link to the FSM, it'd be awesome.

I'm very grateful for your help.

 

[IanH]

there is a 97 FSM in .rar format and a 96, which is the same basically, in .zip

Public - Windows Live

 

[IanH]

you may have to sign in to windows...use your hotmail

 

[beetz12]

Cool, I'll check it out later tonight... thanks!