90 Q45 surges when going up or down hill????

[aliciaford]

My Q runs great on the open road, going uphill it surges. If I accelerate and speed up, it goes away. I noticed the same thing yesterday only quite a bit milder going downhill. Any ideas???

[Infinitiguy19]

Without previous service history I would have to say MAF sensor and connector just clean them Here: http://q45.org/maf.html

Then clean the throttle body: http://q45.org/tbclean.html

Then check your fuel injectors: http://q45.org/ohminjectors.html

And if not done so aready install a external transmission cooler: http://q45.org/trannycooler.html

And most importantlly of all install metal backed chain guides: zerothread?id=25201

Welcome to NICO by the way.

Modified by ppastos at 5:32 PM 8/6/2008
Modified by ppastos at 5:33 PM 8/6/2008

[aliciaford]

Thank you. I will have the hubby check those out. We were thinking it was starving for fuel. I had it serviced at the dealer and they indicated that the hoses needed to be replaced under the intake plenum. Might as well check it all... Again, thanks for the info.

[Infinitiguy19]

No problem you might want to check this out as well if you think its fuel starvation: zerothread/203341.

Do you hear a lot of buzzing comming from the back seat if so then it might be your fuel pump and it might be taking our the fuel pump controller Read this: zerothread?id=273138

[maxnix]

If you have not performed any fuel system nor intake path maintenance, your symptoms are telling you your car is suffering from deferred maintenance.

But the timing chain guide problem takes precedence over all else!

Did you go to Infiniti of Kirkland or Infiniti of Fife?

[aliciaford]

Infiniti of Fife. Chain guides were done a few years ago. My poor car has had so much work done to it, Ive bought it 5 times over, I swear. But I still love her...Thanks for the help!

[Infinitiguy19]

So then you figured out the problem?

[maxnix]

Say hello to Charlie the service manager.

I am not familiar with his technicians down there but he might have one Senior Tech (on who was trained on the G50 in 1989).

If you go to Portland, Eric at Infiniti of Beaverton is such a tech and their prices are a littles less and no sales tax.