Engine Problems it will start but wont run. PLEASE READ HELP!!!

[96Qowner]

Ok so I got home today and installed another FPCU and the car still doesnt start. This time it sounds like its about to run then it stops. I checked to see if the FPCU got burn or the coil and both are in good condition. So what should I do now? HELP HELP HELP !!!

Drat.

A'ight, the pump runs, your FPCU is probably good, new fuel filter ... sounds like you have fuel pressure. Those numbers you gave us can't be fuel pressure at 90-100 lbs, but lets go after the electronics side now, as some others have suggested.

First thing, easiest, cheapest thing is the MAF. Earlier in the thread I gave you this link:

http://www.q45.org/maf.html

If it won't even start, the MAF would have to be in really bad shape, so the main thing would be to check/clean the connector real well. The connections have a bad habit of degrading and you can often wiggle the connector and the engine will surge or stall. Simply pulling it and cleaning it may make a difference - enough to get it started. If you're smelling fuel, it may also be flooding, so it wouldn't hurt to crank it with the pedal to the floor, when it stalls or is trying to catch.

You really should also see what code(s) the ECU is throwing - would help a LOT. Here's a thread that has a post with the code reading procedure in it:

"I don't know if I am reading the codes properly... but this is the process I used:

1) pulled the ecu out so I could see the diode and set screw2) made sure the screw was all the way counter clockwise3) started the car4) turned the car off, turned the key on5) turned the screw all the way clockwise until it stopped6) turned the screw counter clockwise about a quarter turn or so until I saw 3 blinks of the diode7) from that point, the diode would blink 5 slow times followed immediately by 5 fast blinks...

I see that as code 55. I could not get any codes with the car running. Is that normal?"

Engine cutting out, backfire on hard acceleration

This also shows you how much trouble a bad connector can make.

[mexpelon83]

Drat.

A'ight, the pump runs, your FPCU is probably good, new fuel filter ... sounds like you have fuel pressure. Those numbers you gave us can't be fuel pressure at 90-100 lbs, but lets go after the electronics side now, as some others have suggested.

First thing, easiest, cheapest thing is the MAF. Earlier in the thread I gave you this link:

http://www.q45.org/maf.html

If it won't even start, the MAF would have to be in really bad shape, so the main thing would be to check/clean the connector real well. The connections have a bad habit of degrading and you can often wiggle the connector and the engine will surge or stall. Simply pulling it and cleaning it may make a difference - enough to get it started. If you're smelling fuel, it may also be flooding, so it wouldn't hurt to crank it with the pedal to the floor, when it stalls or is trying to catch.

Ok, last night i remembered you told me about the MAF so since I didnt have that spray that it shows in the thred i just got a weed blower and used that to blow the dirt that was there. But I will go to Autozone again and try and find that spray that is pictured on the thred. Also I did notice that the connector that you are talking about the one that goes to the Sensor is broken. so the sensor doesnt stay tight. Its very easy to pull out ot get moved. MAybe replacing the connector would be a good idea??

Also I mentioned that when I bought the car it came with a Viper Alarm but the seller didnt give me the keychain controller... Also when I turn on the key and after I leave the key on "on" the antilock just keeps blinking????

Something I have notice is that the battery goes dead after trying two or three times to make the car run???

[96Qowner]

LOL!

Geez, mexpelon, get serious, man! We're trying to help you here. Do NOT ... EVER ... point a weed blower at sensitive electronic sensors. Geez.

A connector that's "broken" and "doesn't stay tight" ... yeah, that could sure cause some trouble, lol.

And thirdly, the Q45 alternator doesn't provide enough juice to recharge a dead battery. Get a charger on it pronto. Not enough juice will cause all sorts of problems, too.

So, if you haven't already destroyed your MAF, you're gonna need to get that connector fixed. Joe has the little pins and the housing. The prices may not be current, but here are the part numbers for the MAF connector:

38751-123 Pins (you need 3) $1.54 ea 38751-112 Connector Shell $17.08 Total: $21.70

The invoice shows Location/List as BC1A

1-888-216-5328

So, fiddle with that connector - if you can be sure it's tight somehow, try starting it then - AFTER you've charged your battery back up.

Sorry for being amused at your troubles, but we're just trying to save you from expensive dealers and ignorant technicians - bear with us and we'll get this solved.

[StarPD]

LOL!

Geez, mexpelon, get serious, man! We're trying to help you here. Do NOT ... EVER ... point a weed blower at sensitive electronic sensors. Geez.

A connector that's "broken" and "doesn't stay tight" ... yeah, that could sure cause some trouble, lol.

And thirdly, the Q45 alternator doesn't provide enough juice to recharge a dead battery. Get a charger on it pronto. Not enough juice will cause all sorts of problems, too.

So, if you haven't already destroyed your MAF, you're gonna need to get that connector fixed. Joe has the little pins and the housing. The prices may not be current, but here are the part numbers for the MAF connector:

38751-123 Pins (you need 3) $1.54 ea 38751-112 Connector Shell $17.08 Total: $21.70

The invoice shows Location/List as BC1A

1-888-216-5328

So, fiddle with that connector - if you can be sure it's tight somehow, try starting it then - AFTER you've charged your battery back up.

Sorry for being amused at your troubles, but we're just trying to save you from expensive dealers and ignorant technicians - bear with us and we'll get this solved.

Your Viper alarm may be the culprit. Remove it, or at least disconnect it completely, then try again.

If that doesn't work, leaqve it disconnected and try disconnecting the battery and waiting a while before re-connecting it.

If this fails, take it to an Infiniti dealer (on a flat bed only) and have it checked out.

Let us know what the problem is oince you get it resolved. It may help others here.

[mexpelon83]

LOL!

Geez, mexpelon, get serious, man! We're trying to help you here. Do NOT ... EVER ... point a weed blower at sensitive electronic sensors. Geez.

A connector that's "broken" and "doesn't stay tight" ... yeah, that could sure cause some trouble, lol.

And thirdly, the Q45 alternator doesn't provide enough juice to recharge a dead battery. Get a charger on it pronto. Not enough juice will cause all sorts of problems, too.

So, if you haven't already destroyed your MAF, you're gonna need to get that connector fixed. Joe has the little pins and the housing. The prices may not be current, but here are the part numbers for the MAF connector:

38751-123 Pins (you need 3) $1.54 ea 38751-112 Connector Shell $17.08 Total: $21.70

The invoice shows Location/List as BC1A

1-888-216-5328

So, fiddle with that connector - if you can be sure it's tight somehow, try starting it then - AFTER you've charged your battery back up.

Sorry for being amused at your troubles, but we're just trying to save you from expensive dealers and ignorant technicians - bear with us and we'll get this solved.

LOL LOL

Sorry I am just getting inpatient with this freaking car. I had it like this for two months and I am getting tired of having my sister give me a ride everywhere..... I am getting to the desprate point lol...

I should of known better than to use that.... But I already printed out the MAF cleaning steps and I will work on that when I get home ( its kind of hard to work on your car when you get home at 5pm and the sun is almost out. THANKS DAYLIGHT SAVINGS) ha.

[mexpelon83]

Your Viper alarm may be the culprit. Remove it, or at least disconnect it completely, then try again.

If that doesn't work, leaqve it disconnected and try disconnecting the battery and waiting a while before re-connecting it.

If this fails, take it to an Infiniti dealer (on a flat bed only) and have it checked out.

Let us know what the problem is oince you get it resolved. It may help others here.

Ok well the Viper alarm has been disconnected. But this past weekend the car just starting honking like if an alarm had gone off... But like I said the Viper alarm is taken off the car already.

[mexpelon83]

You really should also see what code(s) the ECU is throwing - would help a LOT. Here's a thread that has a post with the code reading procedure in it:

"I don't know if I am reading the codes properly... but this is the process I used:

1) pulled the ecu out so I could see the diode and set screw2) made sure the screw was all the way counter clockwise3) started the car4) turned the car off, turned the key on5) turned the screw all the way clockwise until it stopped6) turned the screw counter clockwise about a quarter turn or so until I saw 3 blinks of the diode7) from that point, the diode would blink 5 slow times followed immediately by 5 fast blinks...

I see that as code 55. I could not get any codes with the car running. Is that normal?"

Engine cutting out, backfire on hard acceleration

This also shows you how much trouble a bad connector can make.

ok you threw me off on the ECU part.... Where do I see those codes at ? All that ECU part went right over my head.......

[96Qowner]

Actually, this is the first thing you or any tech should have done. You'll find the Engine Control Unit (ECU) behind the passenger kick panel. It has a screw and a red bulb. You turn the screw one way and then back, and then watch the bulb blink and count the blinks. Here's the relevant section of the FSM (Factory Service Manual):

EF&EC Section of 1994 Q45 FSM

Start on page EC-50. This is the 1994 manual, but it's enough the same not to matter.

Don't bother trying to start it, just turn the ignition on.

[mexpelon83]

Actually, this is the first thing you or any tech should have done. You'll find the Engine Control Unit (ECU) behind the passenger kick panel. It has a screw and a red bulb. You turn the screw one way and then back, and then watch the bulb blink and count the blinks. Here's the relevant section of the FSM (Factory Service Manual):

EF&EC Section of 1994 Q45 FSM

Start on page EC-50. This is the 1994 manual, but it's enough the same not to matter.

Oh ok I know which one it is.... its located under the glove conpartment right?

Its a box that looks similar to the FPCU ?

[96Qowner]

Yup, that's your best bet right now. Do that first and see what code(s) you get.

I'm assuming you don't want to spend the money on a dealer analysis. For $100 or so, you can get a Nissan or Infiniti dealer to hook up their Consult diagnosis system and get a professional analysis.

[maxnix]

For $100 or so, you can get a Nissan or Infiniti dealer to hook up their Consult diagnosis system and get a professional analysis.

No, that would make too much sense. Back to the leaf blowers!
Modified by maxnix at 9:07 PM 11/7/2007

[mexpelon83]

Yup, that's your best bet right now. Do that first and see what code(s) you get.

I'm assuming you don't want to spend the money on a dealer analysis. For $100 or so, you can get a Nissan or Infiniti dealer to hook up their Consult diagnosis system and get a professional analysis.

oh I wouldnt mind spending the 100 bucks to get that done but I mean I know that they are going to charge me an arm and a leg to fix the problem. Thast why I rather just post this on here and see what some of you guys that have had this kind of car for longer have to say. So far all of you have been great on giving me advise.

Without you I wouldnt of known that there was a FPCU and that it was fried.

I will do the codes when I get home. Tonight.

Also what is a CAS? I have read that earlier in the thread but forgot to ask about it. While you are at it what is the PSV or PCV?

[96Qowner]

CAS is Crank Angle Sensor - Infiniti calls it a CMPS, Cam Position Sensor.

PCV is Positive Crankcase Ventilation - recirculates exhaust gases.

The CAS connector can become iffy just like the MAF connector. The PCV can become dirty.

Here's the complete 1994 manual:

Factory Service Manual FSM for 1994 Q45

The EC section has info on the CAS as well.

[mexpelon83]

CAS is Crank Angle Sensor - Infiniti calls it a CMPS, Cam Position Sensor.

PCV is Positive Crankcase Ventilation - recirculates exhaust gases.

The CAS connector can become iffy just like the MAF connector. The PCV can become dirty.

Here's the complete 1994 manual:

Factory Service Manual FSM for 1994 Q45/

The EC section has info on the CAS as well.

Right on tahnks for the defs. and for the manual last night I was trying to find the manual at Autozone and they didnt have it. They only had Infiniti's sister Nissan.

[1990QOwner]

Right on tahnks for the defs. and for the manual last night I was trying to find the manual at Autozone and they didnt have it. They only had Infiniti's sister Nissan.

Auto Zone isn't going to have a FSM for a 15 year old Infiniti. You will need to find a PDF version on the web or else you can get them off of eBay for $30 or $40 and wait for a week for it to arrive. Did you check all around in your car to see if there is already one in there? Be sure to check the trunk, that is where they usually are.

[mexpelon83]

Auto Zone isn't going to have a FSM for a 15 year old Infiniti. You will need to find a PDF version on the web or else you can get them off of eBay for $30 or $40 and wait for a week for it to arrive. Did you check all around in your car to see if there is already one in there? Be sure to check the trunk, that is where they usually are.

Yeah I kind of figure that out already last night lol..... 96Qonwer already gave me the PDF file I will get that.

[mexpelon83]

Morning All

OK So I worked on the MAF last night and I cleaned out all of the snesors with the spray and I put some Dieletric grease after I was done on each one of them.

So I left some time go by and I tested the car and this time the car was different. This time the car was ready to go and run on the first try it even turned on all the way but then the battery started dying and after the third try the battery was dead again.

So I think that the problem is in either the starter or the alternator? Would you think since the battery was is a couple months old just after three tries.

[96Qowner]

Ok, need more info. The car started and ran? Or I think you're saying it sounded like it might run this time, but never quite caught before the battery ran dead? Yes?

I'm assuming then, that you didn't put a charger on it? Tsk, tsk. Get the battery charged up. It's only a couple months old? When you have a full charge on the battery, try it again. Things are sounding better.

I doubt anything's wrong with the starter, but it's possible you have alternator troubles. Get a full charge on that battery and go from there.

You also didn't read the ECU codes? Tsk, again.

[mexpelon83]

Ok, need more info. The car started and ran? Or I think you're saying it sounded like it might run this time, but never quite caught before the battery ran dead? Yes?

I'm assuming then, that you didn't put a charger on it? Tsk, tsk. Get the battery charged up. It's only a couple months old? When you have a full charge on the battery, try it again. Things are sounding better.

I doubt anything's wrong with the starter, but it's possible you have alternator troubles. Get a full charge on that battery and go from there.

You also didn't read the ECU codes? Tsk, again.

Lol.... recap. I work from 8-5 get home around 530 6pm. So I only have a limited amount of time to work on the car during the week. This week I have been going home and go straight to work on the car.

Yes the car sounds like its getting better....

Yes the car sounded like it might run before the battery started to die.

More on the battery. I went to Autozone on Tuesday night to take the battery to get it tested to see if it was a bad battery and they said that the battery was very low and that it seemed that it was in good condition. they charged it for me for about an hour or so. When I got home i put it on the car so the battery was fully charge.

I also do believe that there is something with the alternator. when I bought the car the guy was in a rush to point out that he had replaced it because it was killing the batteries. I think that this dumbnut never replaced it and if he did it was a bad one or he might of done a trick on it so that it could turn on until he would sell the car.

Now that i recall when I first bought the car and i would start the car. A harsh noise could be heard when I could turn the key on. It would sound like a scraping sound then once the engine would run the noise would stop.

[96Qowner]

Ugh ... that noise doesn't sound like a good thing at all. Prepare yourself for the strong possibility that your guides are trash and that it DID jump a tooth on the timing chain. That noise could very well have been chain noise.

Let's stop all this shooting in the dark and get some codes from the ECU tonight.

If you can get the battery charged back up, just crank it 5-10 seconds at a time. If it almost runs and then dies, press the pedal to the floor and hold it there for the next 5-10 sec crank - do that for a couple tries - see how that goes. If it doesn't catch at all, take your foot off the pedal and try again. Etc.

There's also the possibility, if the guides are bad and it jumped time, that all this cranking will make a bad situation worse - ie, blow the engine. Your call.

Get some codes from the ECU.

[mexpelon83]

Ugh ... that noise doesn't sound like a good thing at all. Prepare yourself for the strong possibility that your guides are trash and that it DID jump a tooth on the timing chain. That noise could very well have been chain noise.

Let's stop all this shooting in the dark and get some codes from the ECU tonight.

If you can get the battery charged back up, just crank it 5-10 seconds at a time. If it almost runs and then dies, press the pedal to the floor and hold it there for the next 5-10 sec crank - do that for a couple tries - see how that goes. If it doesn't catch at all, take your foot off the pedal and try again. Etc.

There's also the possibility, if the guides are bad and it jumped time, that all this cranking will make a bad situation worse - ie, blow the engine. Your call.

Get some codes from the ECU.

If that noise was the time chain why doesnt it do it now?

[96Qowner]

Because it was flopping around before - now that it jumped a tooth, it's tight for now.

... IF it jumped ...

The ECU will tell you. We know basically squat right now.

[96Qowner]

After doing some reading, I'm not sure it's time to panic about the guides. I can't find any other posts with your symptoms. Here's some reading material for you:

zerothread?id=249491

zerothread?id=12551

zerothread?id=71655

zerothread?id=9294

zerothread?id=21947

zerothread?id=710

But with your mileage, and if they haven't been replaced, you're playing with fire. We'll see.

[mexpelon83]

After doing some reading, I'm not sure it's time to panic about the guides. I can't find any other posts with your symptoms. Here's some reading material for you:

zerothread?id=249491

zerothread?id=12551

zerothread?id=71655

zerothread?id=9294

zerothread?id=21947

zerothread?id=710

But with your mileage, and if they haven't been replaced, you're playing with fire. We'll see.

Thanks for taking time to read stuff for my problem.

Yeah it sucks that i dont know if they had been replaced or not before. who knows maybe the pastic was changed to metal covers lol.....

I been doing a lot of reading also but I will for sure do the ECU tonight.

[96Qowner]

When you work on it tonight, take a flashlight and check the color of the sealant around the front engine cover, just for kicks. If it's light blue, the cover has never (or not since 95-96) been off. If it's red or some another color, it has. It doesn't necessarily mean the guides were replaced, though.

More threads on the timing chain guides (slow day at the store today ):

zerothread?id=153670

zerothread?id=164335

zerothread?id=7058

zerothread?id=12941

zerothread?id=46708

And you can call Infiniti Consumer Affairs at 800-662-6200 with your VIN and they will read you their repair history from their dealer database.

[mexpelon83]

When you work on it tonight, take a flashlight and check the color of the sealant around the front engine cover, just for kicks. If it's light blue, the cover has never (or not since 95-96) been off. If it's red or some another color, it has. It doesn't necessarily mean the guides were replaced, though.

More threads on the timing chain guides (slow day at the store today ):

zerothread?id=153670

zerothread?id=164335

zerothread?id=7058

zerothread?id=12941

zerothread?id=46708

And you can call Infiniti Consumer Affairs at 800-662-6200 with your VIN and they will read you their repair history from their dealer database.

Ok I did the ECU test and it gave me a code 55 it would blink 5 times slow and 5 times fast....

Also I checked the front of the engine like you said and there is some red sealant all around the engine.

then last but not least the car turned on the fan started spinning but then after the second try the battery is dead again. So shall we say Altnernator ?

[1990QOwner]

As far as I know than the alternator wont stop the car from running, but I could be wrong. I guess we will 96Qowner answer that.

[96Qowner]

You say the car started and ran? Like, it would have stayed running if you hadn't turned it off?

The red sealant is a welcome sight. It's a bit hard to imagine how any original plastic guides could have lasted 231,000 miles.

If your battery was fully charged for the first crank and dead for the second, you got some serious glitches somewhere, heheh. Something would have to be draining your battery in a matter of seconds - doesn't make sense. I'd take the battery to Autozone and get it tested before I'd look at the alternator. Like 1990QOwner, I've also been wondering about the Viper wiring - thought it might have something to do with the battery not holding a charge.

But it started and ran this time?

[mexpelon83]

You say the car started and ran? Like, it would have stayed running if you hadn't turned it off?

The red sealant is a welcome sight. It's a bit hard to imagine how any original plastic guides could have lasted 231,000 miles.

If your battery was fully charged for the first crank and dead for the second, you got some serious glitches somewhere, heheh. Something would have to be draining your battery in a matter of seconds - doesn't make sense. I'd take the battery to Autozone and get it tested before I'd look at the alternator. Like 1990QOwner, I've also been wondering about the Viper wiring - thought it might have something to do with the battery not holding a charge.

But it started and ran this time?

Yes, it ran for like seconds then it turned off. send time around the fan would just spin but not turn on completly.

I took the battery to autozone already on Wednesday and they said that the battery was in great condition and that I had to check the alternator.

so what does the code 55 mean?

[Q45tech]

Code 55 only means that the sensors the ecu monitors are functioning. They are putting out a signal or voltage...............the ecu is not smart enough to tell if the voltage/signal is correct or not. Unfortunately few sensors are monitor and dozens of things you should know you don't.

Like fuel pressure or even if fuel is flowing into rail and out injectors, whether spark plugs are firing and whether the spark voltage is adequate to ignite mixture.