1997 Q45- wet weather issues/ maybe electrical

[smoke9]

hello, im new to this site and in need of some help. whenever it rains or there is moisture in the air. my car begins to run poorly. when i start it up it runs fine, but after a few seconds the TCS light and the SLIP light will come on. At the same time the car will idle irregulary. It will idle down as if it wants to cut-off, then idle back up. when i put it in the drive position and take off from 0-30 mph it seems as if it wants to stall. When it feels like it wants to cut off the car begins to jerk.im not sure what the problem is. i was told that it could be from the wiring harness getting wet.

[maxnix]

Welcome to NICO, Smoke9!

I guess you have checked all the easy connections at the battery and alternator?

Might be time to visist an specialist automotive electrical shop with the FSM printed or on your laptop.

http://www.nicoclub.com/FSM/Q45/

[smoke9]

yea im trying to figure something out. im searching the wires to make sure there are no bad connections.

[goody90q45]

....... At the same time the car will idle irregulary. It will idle down as if it wants to cut-off, then idle back up. when i put it in the drive position and take off from 0-30 mph it seems as if it wants to stall.

Sounds an awful lot like the Mass Air Flow (MAF) sensor to me. CEL on? Have you pulled the codes? An easy thing to check is the MAF connector. The one in the pic may look different than yours but the idea's the same. The connector and the MAF pins should be free of corrosion and the connector pins should fit tight. When lubed with dielectric grease and tightened properly it shouldn't wiggle up and down more than 1/8". Is the connector's metal clip still in place? A lot of (new) owners start having connector problems after a Jiffy Lube oil change where the lube tech has forced your air filter out of the airbox with the MAF connector attached to the MAF/airbox lid. Tighten up the pins with a pointed tool (small nail).

.........when i put it in the drive position and take off from 0-30 mph it seems as if it wants to stall. When it feels like it wants to cut off the car begins to jerk. im not sure what the problem is.....

Wes is busy with school but if he were here tonight he would say check your fuel pressure. It's probably the fuel pump or fuel pump control unit (FPCU) gone bad. Have you replaced either? How many miles on your Q? Sound like a swarm of bees in your trunk?

Do the easy stuff first (clean up MAF connection) and see if there's any improvement. Get back to us with some maintenance history. Good luck.

[Infinitiguy19]

And check the TCS relays on my Q there located next to the bottom right corner of the battery, They might be missing the seals that prevent moisture from getting in there or they might be dirty.

Welcome to NICO.

[smoke9]

My CEl was on.it readboth knock sensors and, it read O2 sensor. bank 1- downstream. so i had that changed. well it rained yesterday. and my car did not run as poorly. it didnt idle down or anything. but i did notice some small misfiring going on. while siting. the car seemed like it wanted to jump rope a little bit. lol. oh my Q has 178, 898 miles on the Pretty Young thing.

[maxnix]

Reset your ECU, then check for codes when it happens again.

You should have a particular cylinder(s) misfire code.

[smoke9]

check it when the CEl comes on. right!!!

[maxnix]

Yes, or just scan it after it stumbles a few times. CEL will not always illuminate.

[bullittandy]

Yes, or just scan it after it stumbles a few times. CEL will not always illuminate.

Can a tech provide a definitive answer as to whether you can have a code with no CEL?

[Brokenbc]

Can a tech provide a definitive answer as to whether you can have a code with no CEL?

I'm not a infiniti tech but I do for sure know that the knock sensors don't turn on the CEL. They through codes but no light.

I had some stumbling at idle and a loss of power, checked the codes... got P0330(i think that's it) and the other knock sensor code.... I replaced the sensors last weekend and the stumbling is fixed and the power is back. I think i'm getting better gas milage too .

I don't know about the TCS issue though, mine hasn't worked since I bought the car.

[goody90q45]

Can a tech provide a definitive answer as to whether you can have a code with no CEL?

I'm not a tech but..... From the 94 FSM, ECU codes that illuminate the CEL (or don't). The same chart is probably in a similar section of the 97-99 FSM.

[maxnix]

Can a tech provide a definitive answer as to whether you can have a code with no CEL?

I have.

[smoke9]

Is there anyway you can test to see if the knock sensors are bad. i had autozone scan my vehicle and both knock sensors read. im wondering if this could be the misfire problem!!!!.

[smoke9]

Also, as I have realized that the knock sensors DOES NOT affect the CEl. thats weird , but ok!!

[maxnix]

Is there anyway you can test to see if the knock sensors are bad. i had autozone scan my vehicle and both knock sensors read. im wondering if this could be the misfire problem!!!!.

You Ohm test them, then inspect for cracks.

[qship96]

Is there anyway you can test to see if the knock sensors are bad. i had autozone scan my vehicle and both knock sensors read. im wondering if this could be the misfire problem!!!!.

Bad knock sensors do not cause engine mis-fires.

[smoke9]

wet weather issues are still on going- trying to do a self diagnosis of the problem. any suggestions

[maxnix]

Did you check all of your conections?

[smoke9]

getting a diagnostic check done today as well to see how much it will cost to replace knock sensors. so wish her well!!!!

[maxnix]

If you have wrenches, a socket set, an accurate torque wrench and the gaskets, you can do it yourself.

[qship96]

Joe has a smoking deal on knock sensors this month.....almost 1/2 off, better hurry and get your order in!

[smoke9]

well i got my car back today, and it is the TPS that has gone bad. looking for a replacement part as i speak. before it gets to cold here where i live.

[smoke9]

well i got my car back today, and it is the TPS that has gone bad. looking for a replacement part as i speak. before it gets to cold here where i live.

[smoke9]

well i'm back everyone. So i changed the TPS sensor on the car, both of them, and had them adjusted. so now my tcs off and slip light stay on all the time now. and i also scanned the car with a OBDll scanner, and it readU3FFF= Ignition Input off, and P1120= Manufacture Control fuel air metering. im confused as to what to do at this point. this car is frustrating me terribly. I could use some help and suggestions.

thanks, smoke9

[twebster725]

Did you ever figure out what was causing the problem?

My 1998 Q45 with 219K miles has been running like normal and then suddenly when I started it up last night the TCS Off and Slip lights both came on and when I touched the gas pedal the car stalled. It sounds like it is idling normally as long as I don't touch the gas pedal.

I recently had the front struts and wheel speed sensors replaced, but that was over two weeks ago and the car has been running fine. The Infiniti tech I spoke to over the phone didn't think that was a likely cause, but could not give me any ideas of what could be wrong. He just said it sounded "like a complicated issue". The nearest Infiniti dealer is over an hour away so I have an appointment to take it to a Nissan dealer, but the soonest they can look at it is on Monday. I've searched the forum and it appears that quite a few people have had this issue, but nobody has posted any solutions.

[paranoidjack]

If you have wrenches, a socket set, an accurate torque wrench and the gaskets, you can do it yourself.

Jeez Brian, you make it sound like bread, ham, and swiss for a picnic!

It's no picnic!

[miata007]

My car recently also came back with code stating the TPS issue. I actually received 3 codes. See link: zer...7-y33

Following the FSM, I tested the resistance of the TPS and confirm to be bad.The code I was getting were: P1020, P1705, and ??? (related to TPS Tandem).

My car too had CEL on with TCS ABS on as well.Will keep you guys posted once I recieve TPS this week or early next week.

FYI:coils and plugs replaced 1-2 year ago.MAF sensor : replaced 4-5 years ago.KS (2): replace 3 years ago.

007