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View Full Version : HELP!!!

tkrolo
08-03-2002, 02:38 PM
After hunting for the cause for the dreaded hesitation problems, changing numerous filters, plugs, cap and rotor, sensors, etc, I run into more problems.   At approximately 4500 rpms, it starts to bog and aparently misfire.  It sounds as if it is backfiring on the intake stroke!?  I have had a few problems now and then with the mafs connection not being solid enough.  It does sound similar to when you try and start the car with the intake disassembled.  Have checked all the vacuum connections and hoses and they look brand new, no cracks or anything suspicious.  I have been getting codes for 02 sensor and ignition system, but just changed the 02 and cap and rotor.  The car has been running rich, but the plugs don't show much for deposits or abuse.

I don't know where to go from here, besides the &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;(&*!@#$$$$$<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'> Nissan dealer. &nbsp;Somebody save me.
DSC
08-03-2002, 09:23 PM
why would you try and start the car with the intake disassembled?
tkrolo
08-04-2002, 07:23 PM
Obviously not the smartest thing to do; you've never had it torn apart to fix a particular thing and wondered if it would even start or not after making the repair? &nbsp;I've only tried it a few times; also comparable to having the mafs disconnected.
tkrolo
08-06-2002, 12:45 PM
Anyone?
uiuc240
08-06-2002, 01:18 PM
have you done anything beside just a visual check of the vacuum connections? &nbsp;i would do a search online about "auto boost pressure tester" or something similar to that. &nbsp;it'll talk about building a system that will let you use a bike pump to put a little pressure in your lines and listen for leaks. &nbsp;yes, you don't have a turbo, but the principal is the same. &nbsp;holes are holes. &nbsp;also, are you SURE you've checked every vacuum line? &nbsp;even the ones to the EGR valve and BPT circuit?

Eric
tkrolo
08-08-2002, 10:13 PM
I fixed most of my problem!! &nbsp;I followed some advice off a post some time ago about cleaning the mafs with carb cleaner. &nbsp;

After talking to a mechanic friend (Ford), he said most cars have a heating element in the mafs and anything other than air that touches it can cause it to overheat and malfunction. &nbsp;I removed the unit and poured some alcohol over the unit as well as cleaned off several connections, like the tps, mafs, etc. &nbsp;I also took out the AIV and cleaned it out. &nbsp;It didn't appear faulty but it is clean now. &nbsp;

Still having a slight misfire at around 5000 rpms; just feels like it bogs a little. &nbsp;Planning on checking fuel pump and regulator this weekend.