its better to use ngk plugs than bosch ,many have had bad experiences... just go back to ngk

 

So, NGK makes a platinum plug? I know a platinum plug is hotter than a regular plug. I might be just depriving my engine of what it needs. So, Bosch Platinum plugs aren't really platinum? Would it be worth it for me to change my plugs again? another $50. Thanks.

Aaron92SE

 

I am running Bosch plugs as well, and these are old (10,000+ miles) ones. I have seen a dealer about this problem, and his conclusion was a faulty ignition coil. Could be, but I was not ready to put $500 worth of coils in at the time.

However, the first thing they did was to take my Bosch plugs out and eplace them with oem NGKs, and changed the air filter to oem as well. They really are big on oem parts when testing performance issued. The reason I put the Bosch back in is that my car started missing horribly, less than 10K after this test, and I found it was NOT my FPR. It was caused by a FAILED NGK plug. So I put my used Bosch back in and had a smooth running engine again, and was happy, except that the lag was there. I can't remember if I had less lag with all oem plugs working so I'll find out.

I'll go back to oem NGK, and I will post results.

John

 

Now your idea may be possible, I have had this idea with a friend of mine to air condition car engines a while ago. He suggested it to be done by a specialist auto-air conditioner

Now it is a good idea perhapes in theory but most likely to be not possible or to expensive in practice...I am a final year Mechanical Engineer in Australia and was acutally going to do my thesis on this very idea of air-conditioning the car engine, but I did not look into it and did something else. It is a idea worth looking into!

 

Hey you guys over there in the states you can be sure to know that this has to be a fualt or common problem for all the Nissan Maximas!!!

Cause I am from Austrlia and have owned two Maximas (one 90 SE and the one I have now 92 SE)they both have the bogging acceleration problem in hot summer days, and down here in Australia (Sydney) it gets pretty hot, over 40 degrees in summer.

I think everyone should collaborate in finding out how to solve this problem

Cheers

 

You guys might have a temprature sensor thats about to take a dump or is corroded...........

 

Has anyone ever thought to check their exhaust system? I've heard that (with other cars as well) if the exhaust system is clogged (namely the catalytic converter), it will bog down the acceleration of the car. I have a 92 SE (auto) that has the same problem. When I rev the engine in neutral, it spins up fast. The problem (as you guys have seen) occurs under load.

At first I also thought it was the trans, but if 5 speeds also experience the problem, that rules that theory out. It would also make sense that it happens when the car "warms up" because that's when the catalytic converter would reach normal operating temp. Under hard acceleration and in the higher RPM range, the amount of pressure going through the system would slightly overcome the problem, and it will re-establish itself at the lower RPM range (when the trans shifts into 2nd, lets say).


Does this make sense?

I'm going to take it to the shop this weekend & have it checked out.

 

I was also thinkging this. my cat converter is as old as car i beleive (90' Max). But I ruled it out thinking its not a possibility but you have a point. when going fast speeds on highway it fixes itself. when you pop into overdirve. it fixes itself. i beleive you solved the summer dampoing on Maximas =)

 

I cleaned my temp sensor, two weeks ago. In Las Vegas, it's still 110 degrees. I have been driving it, and it helped a lot. I have not experienced the extremely slow acceleration since I cleaned it. Of course, my car is slower on a hot summer day, but, cleaning the sensor helped for me. I popped the red cap off and saw that it was corroded. So, I cleaned it with brake cleaner and put some electrical contact grease on it. After that day, I have not had the problem that I once had before.
I still have to wait until a cool night (80 F) to expect my car to be fast. My acceleration increases dramatically on a cool night. I can't wait until the winter, I think my car will love it. Thanks for your help.

 

Well, I went to minekie (sp?) and had my catalytic converter tested. It flows just fine. :-( That shoots my theory to hell (in this case, at least). Next I'll try cleaning the O2 sensor like Aaron did. HOPEFULLY I will see something different.

 

How much did Minekie charge for the CAT test?

 

can someone show me where this red connector is? like with a pic or something?

 

The guy was pretty cool about it... At first he told me it would be $35 for the cat diagnostic, but after he did the test (took him all of 10 minutes), he said don't worry 'bout it... Not bad!

 

Hey James, the red cap is located about 6 inches in front of your throttle body. It will be the only red cap that you see. It's about the size of your thumb. Use a screw driver or something to get it off. If you have a Chilton's Repair Manual (85-92 Maximas), look on page 4-13 and you will see it points to the Engine temperature sensor. Pop your hood and you will see it. Hope this helps you.

 

I have had my car for 3,500 miles since I posted this thread. I have learned a lot about Maximas within that time.

But, I still hate the fact that my car gets slower when my engine heats up to normal operating temperature. The first 10 minutes I drive my car, it's a beast. After that, it gets slower. I have 1/4 miles time slips to show what I mean.

My first run, I ran a 16.70 @ 84.96 mph; my personal best (cool engine). My second run was 1.5 hour later with a cool engine again; I ran a 16.74 @ 84.25 mph. My third run was 20 minutes later and I ran a 17.14 @ 82.77 mph at normal operating temp.

4 tenths of a second is a VERY noticable difference. Maybe it has a lot to do with the fact that I just raced my car. Maybe if I baby it around town and then race it with normal operating temp, I won't lose 4 tenths. Has anybody figured this thing out? Any tips for me? I am going to the Vegas Drag Strip Sat the 11th. I will find out what kind of increase I got with my Y-pipe and post the results.