This last week my exhaust has been ...well ... "blurping" I guess you could say. It doesnt sound like it usually does under throttle, and when you let off and slow down to stop is makes the "blurp" ...its loud enough to hear inside the cab, and does it almost every time I let off the gas and let the RPMs drop down to almost an idle.

It was having some problems starting this last week as well... it always starts but it would crank up and then almost stall but never actually did...it would eventually level off at 500 rpms..but once I took the chip off it doesnt seem to do it anymore. But the Blurp is still there...you guys think it could be the flowmasters? backpressure? They have been fine for about 15-16k miles

 

I wonder if it's a plugged cat or something restrictive in the exhaust?

Does it only make that noise after everything is up to temp? Or when cold too?

Also, after driving and up to full temp, you might try running it kinda hard for a few minutes and then pulling over and seen if the cats are glowing red hot. (worked back in the 70s )

WOT

 

I had it at the track last saturday and it was making the sound every now and then...I only notice it during normal driving, but normal for me does include a 0-60 blast every now and then. It just doesnt sound right at any rpm to me, but the weird blurp only happens when I let off the pedal and let her whine down for a stop...I dont know if it will do it right when I start it up, but it does it for sure 10 mins afterward.

I will give her a good romp before I get home and see what I can see on the underside as far as "red hot" cats. Im starting to wonder if the chamber design of the mufflers isnt causing it...I just dont know why it would take so long to cause a problem.

 

Mine's been doing that almost stall thing when I start it also. I just recently took off the stock exhaust so Im just dumping out the catpipes. I also reset the computer by disconnecting the battery and removed the boost dump plug thingy (the electrical one). Do you guys think its anything to worry about?

 

Im against the boot bypass idea..but thats just me. The starting problem has become less and less as my stock computer seems to be re-learning at the moment...I disconnected the battery for about 15 min after I took off my superchip

 

my dad's 03 stated doing the same thing. 2k miles, and jdm full exhaust. Noticed it first started letting off to slow down for an exit on the highway, seems to misfire. Also,very uneven idle, goes up and down.

Changed the MAF(had an extra laying around)...........nothing. Made sure all the coil packs were seating, still nothing. Adjusted the tps, nothing. My guess right now is that the header gaskets are leaking and throwing the 02 sensors off, causing it to run super rich. Don't know if that may be your problem, but what you described is the exact same thing.

 

I still have the stock manifold with the only change being a cat back with dual flowmasters... I was thinking about taking them off just have it come out the cats to see if it changes.

 

bump

 

Could the "burp" you are hearing be a 'backfire'? If so, look for:

1. EGR system not functionong properly
2. Ignition timing incorrect
3. Damaged valve springs or sticking valves
4. Vacuum leak at the intake manifold or vacuum hoses.

The idle problem may just be a dirty IAC???

Dan

 

Ill check as many as I can, Im not a mechanic by any means. I dont think the IAC is dirty though, I cleaned it out monthes ago.

 

Could be reversion? Which is normal? IE when you floor it and then let off suddenly you hear a burbling noise....

 

its not that, I know what you mean though...its comparable but much more severe sounding. I took off my IAC and cleaned the hell out of it, I cleaned my throttle body since it was so filthy from when I left the damn boot half on for a week , cleaned the inside of the boot and the filter, new oil in the k&N. I havent started it up yet since its so late and all...Ill see if it any better on the way to work tomorrow

 

i am running mufflerless just nothing from the cats back. I get a burp like that when i let off and sometimes on a hard shift. I dont know what it is. I am under warranty so if it breaks, ill take it back. No chip for me as of yet! If something happens i will let you know. My truck also hesitates when i turn the key all the way. It will hesitate till l let go of the key and it will fall back in place and start. I dont think that is a problem but who knows? if it runs... FAST, i dont care. Ill just let for fix their *** up! No mods for me... that can be traced.

Vinny

 

Well it seems to have gotten better...I didnt hear any loud burps this morning on the way to work. It started right up with no hesitation as well...Im sure Im on the right track...but I may need to to take off the plenum to clean it inside better...

does anyone think carb/throttle body cleaner spray would bother the blower if some was sprayed inside the plenum when I was cleaning the TB? I didnt have the right socket to get the bottom screws out of the TB so I left it on and did the best I could that way.

 

anybody have any IAC threads handy? Like where it is and how to clean it? I cant search cuz its under the 3 letter min.... and i don't know what it stands for sorry