# '89 Sentra GA16I Idle & Fuel? Problems



## Quark (Aug 20, 2005)

Okay, I've searched and watched these forums for weeks now hoping that someone would have/had the same symptoms I'm having but nothing seems to fit exactly, so if I've missed the "easy fix" posted 1000 times please forgive me.

First, some history. The vehicle is an 1989 Sentra GA16i with ~165K miles, 5-spd manual, regularly maintained. The car had been running perfectly up until I refueled, drove about 20 miles, and then parked it. The next day when I started it up it made a pinging noise from the engine compartment like rocks in a dishpan when it first started (hasn't done that since) and wouldn't stay running. It would always restart immediately, would accelerate, although "hesitantly", but would die if left at idle. When I drove the car it ran very poorly. It was slow to accelerate even with the pedal to the floor. It would gradually pick up enough speed to back off the throttle but not like it should, and if you were attempting to climb a slight grade the speed would continually decrease no matter how much throttle you gave it as if you didn't even have your foot on the pedal. I also noticed the engine seemed to heat up quicker and run much hotter than it normally does even after the cooling fan comes on.

I've drained the fuel from the tank thinking it may have just been bad gas. No help. I've replaced the plugs, wires, cap/rotor, fuel filter, pcv valve, a weeping heater hose and smaller coolant hose from the bottom of the TBI running up to the side, a partially collapsed vacuum line to the anti-backfire valve, the 02 sensor, and replaced the Catalytic Converter with a straight pipe. None of this has solved the problem. It doesn't run quite as bad while driving/accelerating now but still is pretty bad and still won't idle. Though I have noticed something about the idle that may have been present from the start. If you keep restarting the engine or idle it up to keep it running, after a while it will idle without dying. Not very smoothly, but it does idle, at least while parked. It will still die sometimes when coming to a stop. I havn't checked the timing nor the fuel pressure. I have checked the computer for trouble codes and there are none and ran it thru the several different diagnostic modes as listed in the Chilton's manual and as near as I can tell everything seems to check okay. 

I've read several threads about the Air Flow Meter (AFM), Coolant Temperature Sensor (CTS), and several other possible culprits, but none of the symptoms, at least that I've found, seem to fit exactly. I've been watching eBay for a Factory Service Manual with no luck so far, and I've been checking local junkyards in an ever expanding radius, but so far no luck there either except for one that looked to be in extremely poor condition with dirt and oil all over everything so that is my option of last resort. If I have to buy something new instead of used I'd like to at least have it nailed down pretty good before doing so, so any tips, tricks, suggestions to narrow things down would be appreciated. 

I'm sure, after all that I've been through with this bugger that I probably left something out and if so I'll update as needed. Thanks!

BAHHH! Ended up posting this in the wrong forum. Could I get a mod to move it please?


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## Zen31ZR (Mar 24, 2004)

Hopefully I moved this to the right section. 


For what it's worth, I'd do a compression test on it. Also make sure the cam and crank marks are all lined up properly. Eliminate the possible mechanical problems first.


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## astreamk1 (Apr 16, 2004)

Zen31ZR said:


> Hopefully I moved this to the right section.
> 
> 
> For what it's worth, I'd do a compression test on it. Also make sure the cam and crank marks are all lined up properly. Eliminate the possible mechanical problems first.



X 2, check your timing. The GA16i is prone to timing chain/guide issues at higher mileage. Maybe you lost one of the guides and the chain skipped ?

might explain all the noise your heard. if you take the valve cover off, you might be able to look down in there and see what's going on ?


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## Quark (Aug 20, 2005)

Thanks for the input. Will see if I can find a timing light.


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## Biscuit (Mar 5, 2005)

If the chain skipped it wouldnt run I dont beleive...


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## dreamteam (Jul 29, 2005)

I will concur on the timing chain.
The noise you described sounds like what happens when the 
chain jumps.
If i remember right, your timing will now be retarded about 12 degrees.
You can twist the distibutor ahead but that will not cure the problem.
The spark will be better, but the valves will be out of synch.
Time for a new chain?
Be sure to get new guides too.


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## bob89sentra (Sep 15, 2005)

I agree with the timing chain skipping a tooth. it would cause the valve timing to be off, and make the car run Doggish. (slow to pickup+ no power)
though without changing the IGN timing to compensate for the valve timing I don't know how it could run. Do a compression test to see if mabe the head gaskit is blown. also hook up a vacuume gauge to the intake manifold and see if there is flutter, low , or inconsistant vacuume. The chiltons manual can help you diagnose wheather it is leaking valves, timing off, flat cam, or IGN timing off. keep us posted
Bob


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## astreamk1 (Apr 16, 2004)

we had an 87 Chrysler New Yorker with a 2.2l Turbo. as it got older, they were prone to skip teeth on the timing belt. still ran, just ran like shit. happened 2 or 3 times before we got rid of it. what a POS !


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## bob89sentra (Sep 15, 2005)

:topic: couldn't be as bad as the Chrysler Aries K car I used to have. Skipped theeth twice, then the new belt broke. I thought since it was non interferance it was a good car. Replaced the belt again, and after about two weeks the cam SHEARED off!!!!!??? Now that was a POS!


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## 4pt9fiero (Jul 5, 2005)

I would not be that hasty with the timing chain. My Sentra is exhibiting similar symptoms - rough idle and occasional stalling when coming to a stop. Mine happens more when it is chilly outside. I also had the timing chain noise going on (bad guides - one guide was in 5 pieces), opened it up replaced chain, guides and tensioner. Checked timing everything seems right - start to drive again - same symptoms as before - rough idle, and ocassional stalling when coming to a stop. I also have replaced all the vacuum hoses, new fuel filter, air filter, plugs (NGK), wires, cap and rotor. I have also recently replaced the alternator, and have added some new ground wires - still same problem with stalling and rough idle. This weekend I WILL locate and replace the PCV Valve to see if that helps. If this doesn't do it I have found a fuel pump/sending unit at a JY for $75 I will do try that next weekend. 

Apart from this problem - I love my Sentra - I just wish it would stop rusting!!!


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## dreamteam (Jul 29, 2005)

4pt9fiero said:


> I would not be that hasty with the timing chain. My Sentra is exhibiting similar symptoms - rough idle and occasional stalling when coming to a stop. Mine happens more when it is chilly outside. I also had the timing chain noise going on (bad guides - one guide was in 5 pieces), opened it up replaced chain, guides and tensioner. Checked timing everything seems right - start to drive again - same symptoms as before - rough idle, and ocassional stalling when coming to a stop. I also have replaced all the vacuum hoses, new fuel filter, air filter, plugs (NGK), wires, cap and rotor. I have also recently replaced the alternator, and have added some new ground wires - still same problem with stalling and rough idle. This weekend I WILL locate and replace the PCV Valve to see if that helps. If this doesn't do it I have found a fuel pump/sending unit at a JY for $75 I will do try that next weekend.
> 
> Apart from this problem - I love my Sentra - I just wish it would stop rusting!!!


Have you run the codes on the computer?


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## mille-16i (Jun 16, 2004)

Idle Air Control it may be dirty or faulty in both cases or the chain I would say pop the top and look at everything may have something ascew in the valve train busted rocker or something?


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## NAstyed (Nov 22, 2004)

dreamteam said:


> Have you run the codes on the computer?


Speaking of Codes, do i need a special tool for reading my car's codes?, how can this be performed by a novice?


Thanks!


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## bob89sentra (Sep 15, 2005)

Before you mess with the computer get a list of codes and the programs for your car. If you select the wrong program you could delete the error codes. Under the passenger seat take off the plastic cover from the computer. Then slide the seat all the way foreward. On the back of the computer there is a hole in the housing. Inside there are two LED's (one red, and one green) and a POT. To check the codes turn the ING to Run and turn the pot with a small screw driver counterclockwise the green LED will start to blink in a sequence of numbers. As memory serves me you want the third one (three blinks from green) to select the program turn the POT clockwise after the program you want flashes. then you can look up the codes it gives you to see what the problems are. I think that 5 green and 5 red means "Normal Operation"
Correct me if I am wrong this is off the top of my head from about a year ago.


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## NAstyed (Nov 22, 2004)

bob89sentra said:


> Before you mess with the computer get a list of codes and the programs for your car....



Where can i get this for a 1990 2dr Sentra?


Thanks for the info! :thumbup:


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## dreamteam (Jul 29, 2005)

www.chiltonsonline.com


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## bob89sentra (Sep 15, 2005)

I went to the auto shop that I used to work at, and they printed it out for me. They were using a snap-on computer database. I will go home today and see if I can find the info, I will let you know what I find. My car is an 89, but the codes are the same as the 90. Assuming you have the GA16i right?


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## Quark (Aug 20, 2005)

Diagnostic Trouble Codes - 1990 Nissan

11 Crankshaft Position Sensor 
12 Air Flow Meter 
13 Engine Coolant Temperature Sensor 
14 Vehicle Speed Sensor 
21 Ignition Signal 
22 Fuel Pump 
23 Idle Switch 
31 Engine Control Unit 
32 EGR Function 
33 Oxygen (O2) Sensor 
34 Knock Sensor (Turbo Only) 
35 Exhaust Gas Temperature Sensor 
43 Throttle Position Sensor 
45 Injector Leak 
51 Injector Circuit 
54 A/T Control 
55 No Faults In Memory 


Step 1. Access the ECU and position it for observing the diodes.

Step 2. If the engine does not run, turn the key on and proceed to step #4.

Step 3. Start the engine and warm it to operating temperature then idle.

Step 4. Turn the diagnostic mode selector on the ECU fully clockwise until both diodes flash 3 times then turn the selector fully counterclockwise. The ECCS system is now in mode 3.

Info borrowed from HERE.


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## NAstyed (Nov 22, 2004)

Yes, mine is a GA16i.


Thanks for the Codes, i'll see what my car tells me today.


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## bob89sentra (Sep 15, 2005)

Ahh.. I just got home, and found my Info. Thanks Quark for fillin it in for me.  
Looks like my memory isn't too bad. I just got the direction you turn the POT wrong.


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## dreamteam (Jul 29, 2005)

Quark said:


> Diagnostic Trouble Codes - 1990 Nissan
> 
> 11 Crankshaft Position Sensor
> 12 Air Flow Meter
> ...


Nice goin' Quark, and thanks for the link......


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## Sentrawagon (Jun 6, 2005)

can any one help me out, I was looking at my trouble codes and I have two wierd ones one is: 1 red and 4 green, 2: 2 red and 5 green. if any one can help me out it would be nice. thanx


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## dreamteam (Jul 29, 2005)

Sentrawagon said:


> can any one help me out, I was looking at my trouble codes and I have two wierd ones one is: 1 red and 4 green, 2: 2 red and 5 green. if any one can help me out it would be nice. thanx


If you did the test correctly, this would indicate code 14 speed sensor, and,code 25 AAC valve. That is if you have a ga-16i.


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## Sentrawagon (Jun 6, 2005)

dreamteam said:


> If you did the test correctly, this would indicate code 14 speed sensor, and,code 25 AAC valve. That is if you have a ga-16i.


Thanx for the reply, that's what I thought it was but I wasn't 100% sure. Thanx again for the post.


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## Sentrawagon (Jun 6, 2005)

dreamteam said:


> If you did the test correctly, this would indicate code 14 speed sensor, and,code 25 AAC valve. That is if you have a ga-16i.


Ok, so I guess I was wrong about you guys knowing what you are talking about, but then again, some of you do. So, don't take this personally, but you people should really look at the facts before you start writing things down. First off, I HAVE A GA-16-I. IT IS IN AN 89 NISSAN SENTRA, AND IT IS A 5 SPEED. Secondly, I do own a Haynes repair manual and my uncle also works at Nissan. I am not saying I know everything about Nissans but I am a car enthusiast so I do know quite a bit about vehicles in general. OK, now on to my real problem, the engine codes. I've looked at the Haynes manual and it says there is no vehicle speed sensor for my car. So, I guess if anybody has the correct engine codes for my GA16I, please let me know. Thanx.


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## Quark (Aug 20, 2005)

Sentrawagon said:


> Ok, so I guess I was wrong about you guys knowing what you are talking about, but then again, some of you do. So, don't take this personally, but you people should really look at the facts before you start writing things down. First off, I HAVE A GA-16-I. IT IS IN AN 89 NISSAN SENTRA, AND IT IS A 5 SPEED. Secondly, I do own a Haynes repair manual and my uncle also works at Nissan. I am not saying I know everything about Nissans but I am a car enthusiast so I do know quite a bit about vehicles in general. OK, now on to my real problem, the engine codes. I've looked at the Haynes manual and it says there is no vehicle speed sensor for my car. So, I guess if anybody has the correct engine codes for my GA16I, please let me know. Thanx.


Sounds like you have the same vehicle as I do. The trouble codes are pretty close to the same as the '90 model and I've pasted the info below (As found at the site I posted a link to further up this thread). This chart has no reference to a code 25 and it also differs a bit from the Chilton's code chart as listed on Autozone's site, which does show a code 25 (AAC Valve), but, some of the other code info doesn't exactly correlate. Perhaps someone can provide the definitive answer from a factory manual. Speaking of which, do yourself a favor and use that Haynes manual to line your birdcage with. Its about 3 steps below useless. A lot of the information and most of the diagrams are completely wrong for an '89. It'll have you chasing stuff that you don't even have wondering why its not where it says it is. A factory service manual would be the best but barring that get a Chilton's. I picked up a Chilton's at the auto parts store for about $15 but still looking for a factory manual. In the interim, the Autozone web site has the Chilton's manuals online HERE. 


Diagnostic Trouble Codes - 1989 Nissan

11 Crankshaft Position Sensor 
12 Air Flow Meter 
13 Engine Coolant Temperature Sensor 
14 Vehicle Speed Sensor 
21 Ignition Signal 
22 Fuel Pump 
23 Idle Switch 
31 Engine Control Unit 
32 EGR Function 
33 Oxygen (O2) Sensor 
34 Knock Sensor (Turbo Only) 
42 Fuel Temperature Sensor 
43 Throttle Position Sensor 
45 Injector Leak 
55 No Faults In Memory 

1 Access the ECU and position it for observing the diodes. 
2 If the engine does not run, turn the key on and proceed to step #4. 
3 Start the engine and warm it to operating temperature then idle. 
4 Turn the diagnostic mode selector on the ECU fully clockwise until both diodes flash 3 times then turn the selector fully counterclockwise. The ECCS system is now in mode 3

Mode 3 is to read out the codes. Mode 4 is to erase previously stored codes.


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## Quark (Aug 20, 2005)

And this is what Chilton's says about the VSS ...



> The reed switch type VSS is part of the speedometer assembly, mounted to the rear of the instrument cluster. The shaft of the reed switch is turned by the speedometer cable connected to the rear of the instrument cluster. The reed switch has a small magnet attached to it which causes the reed switch to close every time the magnet sweeps past the reed switch. The typical reed switch VSS is connected to a regulated 5V direct current supply, resulting in a switching direct current (DC) square-wave output signal. The VSS output signal frequency will be directly proportional to vehicle speed and is carried to the ECM through the wiring harness.


And how to test its operation...



> 1. Check the speedometer operation.
> 
> (a) If the speedometer is not functioning, check speedometer cable and begin with speedometer assembly testing. Repair or replace necessary components.
> 
> ...


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## dreamteam (Jul 29, 2005)

And........you do have an AAC valve. 

It is called Auxilliary air control valve. 

It controls the idle by the pulses from the ecu which open or close it for more or less air into the idle circuit. If it is not working correctly, the idle will be uneven or too fast or too slow.

CLean it first, don't loose the spring.

If that doesn't work, get a new one.

Or, you can measure the resistance between the two terminals with an ohmmeter. It should be 10 ohms.

And.......what are you complaining about???


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## Sentrawagon (Jun 6, 2005)

I didn't say that I didn't have a AAC valve. I said that I don't think I have a VSS.but thanx for all the help.



dreamteam said:


> And........you do have an AAC valve.
> 
> It is called Auxilliary air control valve.
> 
> ...


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