Popping sounds coming from my exhaust when I take my foot off the gas and slight engine breaking when I take my foot off the gas in 3rd or 4th gear. Also I've been noticing it has been taking forever for it to shift in to 4th. It wont shift into 4th until I hit about 80 or 90mph. I have 176k on it now and the trans was completely rebuilt at 155k. Can you guys give me some ideas of what might be wrong?

 

3.0 or 2.x

 

The popping sound is most likely back pressure

 

To clarify popping is backfiring right? I used to get that from carbon buildup. Top engine cleaning would be recommended if so

 

I'm was thinking about getting a high flow cat but now I want a test pipe instead. First question, does it need to have a port for the o2 sensor? #2, do I need an o2 sensor? #3, do I have to change anything with the ECU? Thanks for all you answers

 

3.0 I cleaned the throttle body, intake manifold, and ERG port about 1000 miles ago. I do get a lot of back pressure after hard acceleration. When I cleaned everything I didn't take the EGR valve off before I cleaned the port that's on the block/engine. Could that be my problem?

 

Also it doesn't feel like back pressure when I take my foot off the gas in 3rd or 4th gear. I've driven a manual before and it feels just like engine breaking.

 

I don't have any experience with test pipes, but I had to drill a hole and do a defouler on my high flow cat to not throw an error

 

I can only comment on the engine braking. Too me, based on what my 3.0 does, this is a normal occurrence. I also get engine braking when taking my foot off the gas in 3rd and 4th. I believe the reason is that the torque convertor stays locked up above 40 mph when your foot is off the gas and creates a similar feel to a manual transmission. Don't know about the popping noises.

 

I just installed my test pipe. I got a CEL eliminator from weapon-r. So far so good. My car is a lot louder and has picked up some acceleration.

 

I just put a test pipe in can now the I only have alittle back pressure. And also ever since I put the pipe in I haven't been having engine breaking and the shifts are alittle smoother.

 

I put a test pipe on my CL and now I'm only getting 10MPG

 

I would never, I used a high flow cat and had a defouler bung welded on so I don't throw codes. Is your CEL coming on?

 

That sounds pretty bad, even when my car was running pig rich it did better than 10mpg. Something else must be wrong. If your O2 sensor is reading correctly it should notice the fuel being dumped like that.

 

^ He didn't use the o2, I think that's why he's running so rich

 

My CEL hasn't come on yet and its been a month or two since I put the test pipe on and I'm still only getting 10mpg. I'm going to try and adjust my CEL eliminator and see if that does anything. If not I know theres a way to hook something up to the ECU to trick it

 

did you reset the ecu after installing?

 

yeah I have a scanner that works on my phone. Its like a OBD2 flash drive and I can use a app on my phone to check codes and flash the ECU