Qx4 Unknown Problem

[ImBradyIRock]

I have a 97 infiniti qx4, and I love it, but there are a few problems with it that I need help answering. I had my TPS replaced about 2 months ago, and besides basic maintenance haven't done anything to it.

Most of these problems occur on the freeway, but are becoming more frequent.
1. When shifting into second, say during heavy traffic, the car bucks at about 1500 rpms. It's a noticeable jolt and will push you forward.
2. When I take my foot off the gas coming onto an exit ramp, or anywhere that's 45mph or more, and start to go into a coast, the rpms drop normally, until they hit 1k, then they surge up to 1500 then back down to just then back up, and will continue until I either brake or accelerate, but sometimes stop on they're own. I can also physically feel it when they drop, almost as if I'm braking then releasing the brake. And I can feel that the whole time.
I've gone to 2 different mechanics and have shown them a video I have, one suggested buying a new computer so it'll throw a code. No thanks. Another said its my instrument cluster, but that's not right since I can feel it. So my 2 mechanics have been no help at all.
My gas mileage has also gone down significantly. I haven't had the car that long, and so far it's been a nightmare and I'm scratching my head at all of it.
If anyone has any ideas its greatly appreciated. I would love any and all suggestions.
I'll try to find the video and post it up in a second.

Thank you guys!

[ImBradyIRock]

Heres a link to the video.

http://m.youtube.com/watch?feature=yout ... tube_gdata_

[Buzzman]

Sounds an awful lot like what happens when the MAF is going bad. I'd start there first.
Also, how many miles on it, and is it throwing any codes?

[ImBradyIRock]

It has about 150k on it, but no codes. Do you think I should just clean the MAF first? How do you suggest going about it? I've looked online everywhere for an answer to this, but nothing solid enough to make me want to throw money down a hole.

[Slumpert]

First thought was transmission issues but if your seeing sudden drop in gas mileage then I would look closely at EGR / Idle air / vacuum leaks diagnostics first.

MAF cleaning is always good thing just be sure to use MAF spray

[04pathse]

It has about 150k on it, but no codes. Do you think I should just clean the MAF first? How do you suggest going about it? I've looked online everywhere for an answer to this, but nothing solid enough to make me want to throw money down a hole.

Wouldn't hurt to clean it . You can buy some CRC MAFS cleaner spray at most automotive stores for around 5 bucks.
Be sure to reset the ECU by disconnecting the battery for a few minutes after cleaning the MAFS.

[ImBradyIRock]

I removed the MAF and turned the car on, it threw a code and the car idled like garbage. I also inspected it and it seemed clean, silver and polished look. So I don't think it is that. What should I do now guys?

[Towncivilian]

What is the condition and level of the transmission fluid?

[ImBradyIRock]

I'm not sure. I know that it can sometimes mess it up to get it changed. But I think I have fluid. Should I get it changed? I was planning on changing my oil tomorrow anyways.

[Towncivilian]

If a transmission begins to exhibit failures after a fluid change, it was on its way out anyway. I'd suggest changing the fluid, absolutely. A drain & fill will take about 4 quarts (1 gallon) of fluid. What ATF do you have available to use?

[ImBradyIRock]

Im not sure what type is available, but im going to an O'Rileys; do you know what kind to get from there?

[Towncivilian]

I'd imagine they have Valvoline MaxLife Dex/Merc ATF or Castrol Transmax Import Multi-Vehicle. I'd go for either, probably leaning toward MaxLife since it's full synthetic.