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

[96Qowner]

Rather defeats the purpose of IoM, doesn't it?

If that is the offical stance, time to combine them again.

Yeah, I dunno, Brian. More and more IOM threads are non-Q45, and fewer NICO Q45 owners are reading and posting there. I think it should stay for the sake of all other Infiniti models, but I wouldn't mind seeing all Q45 threads posted here in the Q45 Forum.

Meanwhile, it's ok with me the way it is.

[96Qowner]

I am thinking of buying another one and try to fix it myself.... I like these cars.

Ok, this would be a good time to bring up the chain guide issue with you.

In the 90-93 series, the timing chain guides were backed with a plastic, not unlike a lot of other manufacturers at the time. Unfortunately, over time, degraded oil (from careless oil change intervals, heating, etc) reacts with the plastic, making it brittle and susceptible to breaking - not always a good thing, heheh. The timing chain then skips and drives pistons into valves - kaboom - sudden death. This can happen at any time, even on startup.

So, every 90-93 owner eventually MUST replace the chain guides with the newer metal-backed ones or he'll fubar his motor - you included. The repair runs somewhere over $1000.

Sorry. But let's get it running first. Meanwhile, read everything under "Chain Guides (CRITICAL for 1990-1993)" on Q45.org:

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

[mexpelon83]

Ok, this would be a good time to bring up the chain guide issue with you.

In the 90-93 series, the timing chain guides were backed with a plastic, not unlike a lot of other manufacturers at the time. Unfortunately, over time, degraded oil (from careless oil change intervals, heating, etc) reacts with the plastic, making it brittle and susceptible to breaking - not always a good thing, heheh. The timing chain then skips and drives pistons into valves - kaboom - sudden death. This can happen at any time, even on startup.

So, every 90-93 owner eventually MUST replace the chain guides with the newer metal-backed ones or he'll fubar his motor - you included. The repair runs somewhere over $1000.

Sorry. But let's get it running first. Meanwhile, read everything under "Chain Guides (CRITICAL for 1990-1993)" on Q45.org"

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

Damn..... so it would be best to replace that plastic with a metal backed ones before they break right?

I hope that this is not that case on mine. The mechanic that we have known for over 20 years said that the timing chain was good and that there was nothing wrong with it.... But i will check the plastic and get the how to guide ( if there is one) on here and replace it while I am at it. I dont want to run any risk. I did forget to mention that the engine has 231,000 + miles on it.

[maxnix]

Meanwhile, it's ok with me the way it is.

Which is?

[maxnix]

If you read the original post you'll see that the second person who ran a diagnose said that the belt had skiped. and that I had to get that replaced.

That "person" not being a Senior Infiniti Technician, I presume?

How would he know without removing the front timing chain covers and inspecting the timing of the camshafts?

Timing belt? Reallly? Shoudl be a clue to run the other way!

[mexpelon83]

Which is?

I really do apperciate all of the people that have comment on the thread but i find it mean that there are others that instead of giving there comment about what the problem could be only come and leave negative comments. That is rude. I am sure that you werent born knowing everything that you know already.... Why dont you cut some slack to others like myself that are trying to learn.

[96Qowner]

Which is?

... semi-redundant, neglected by the regulars, and awkward for new posters.

I was the only one to answer mexpelon83 for the first 4 hours on IOM, during morning hours. 1990QOwner chimed in only after I posted a link from Q45 Forum. Dennis is the only other regular to comment on the IOM thread, and that was early this morning, almost a day later.

But we work it out. I'm fine either way. I DO think it would be better to encourage all Q45 related threads to be posted in Q45 Forum - seems more intuitive that way.

[96Qowner]

Why dont you cut some slack ...

Heheh, maxnix isn't the biggest slack-cutter on the Forum, mexpelion - don' take it personally. Brian is one of the very most veteran posters on NICO, and the Yahoo Q45 forums before that, and probably some other forum before that - a history going back at LEAST 6 years. He's assisted countless posters over those years - a VAST historical knowledge of the cars and their issues.

[mexpelon83]

Heheh, maxnix isn't the biggest slack-cutter on the Forum, mexplelion - don' take it personally. Brian is one of the very most veteran posters on NICO, and the Yahoo Q45 forums before that, and probably some other forum before that - a history going back at LEAST 6 years. He's assisted countless posters over those years - a VAST historical knowledge of the cars and their issues.

Yes, I do understand but just like people learn about fixing cars people should also learn about people skills.

[maxnix]

I DO think it would be better to encourage all Q45 related threads to be posted in Q45 Forum - seems more intuitive that way.

Then at least let's fold the IoM thread into this one. That would help the poster as he is quite confused.

Secondly, let's fold Infiniti General and IoM into Q45, at least the Q45 posts of which there are thousands.

[96Qowner]

Then at least let's fold the IoM thread into this one. That would help the poster as he is quite confused.

Ok, I merged the two threads into this one on Q45 Forum - didn't want to mess with 'em until they'd played out first.

[DrewQ45]

I have two FPCUs in the parts forum if needed...

zerothread?id=280391

[mexpelon83]

I have two FPCUs in the parts forum if needed...

zerothread?id=280391

Thanks for letting me know Drew. I got a few from yunk yard today. If none of them work I will let you know I need one. How much are you selling them for?

[1990QOwner]

If you got em from a junk yard than be prepared to replace them again soon unless you got em of of a fairly new car.

[96Qowner]

Actually, very few (if any) posters have had trouble with used FPCUs. Of course, they're all getting older now ...

If you open them and see no sign of overheating, they're usually good until the pump heats 'em up again.

[1990QOwner]

I guess I'm one to be talking, I put a used one on mine but like 96Qowner said, I opened it up and there was no signs of damage by heat. It has worked great ever since. I would not do a FPCU without doing the pump also.

[DrewQ45]

I've sold many of these without a single complaint. I open every one and check it first.

$65 shipped.

[bullittandy]

Heheh, maxnix isn't the biggest slack-cutter on the Forum, mexpelion - don' take it personally.

Don't say this.

[mexpelon83]

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 !!!

[1990QOwner]

...HELP HELP HELP !!!

Everyone already knows that you need help .

OK, so you have done the FPCU, and you know that the one that you installed is in good condition or at least working properly?

Have you checked the fuel pump it's self? Have you done a fuel pressure check? Once you have done all this than you can cross the fuel system off of your list.

[mexpelon83]

Everyone already knows that you need help .

OK, so you have done the FPCU, and you know that the one that you installed is in good condition or at least working properly?

Have you checked the fuel pump it's self? Have you done a fuel pressure check? Once you have done all this than you can cross the fuel system off of your list.

Yes it is.... Cause when I turn the key on I hear the pump working. I hear that noise on the back. About the fuel pressure test , yes that was done already. Also I can smell the fuel after I keep on trying to turn on the engine.

[1990QOwner]

... About the fuel pressure test , yes that was done already. Also I can smell the fuel after I keep on trying to turn on the engine.

How much PSI was in the fuel line when you did the test? And was the test done after the fuel filter?

[mexpelon83]

How much PSI was in the fuel line when you did the test? And was the test done after the fuel filter?

I dont remember what the PSI was I didnt do it myself. The Fuel Filter was changed way before I started having problems with the car.

[1990QOwner]

Was the pressure checked by a professional? Is it possible that the fuel filter was a cheap one and is plugged again? How recently was it replaced?

[mexpelon83]

Was the pressure checked by a professional? Is it possible that the fuel filter was a cheap one and is plugged again? How recently was it replaced?

I dont think it is cheap i got it at Autozone and it was a bosch fuel filter. it was replaced back in September.

[1990QOwner]

So the fuel pressure test was done recently?

[mexpelon83]

So the fuel pressure test was done recently?

Yes, I believe it was the Fuel Pressure.... that was done last month. I have had the car only for three months so all of the done that has been done to the car or test have been done from September til now.

Would having a Viper alarm have anything to do with the engine not starting completely? the car came with a Viper alarm with no alarm keychain control.

[1990QOwner]

In order to completely rule out the fuel system out you MUST do a fuel pressure check. After that if it still doesn't work than you will need to have the more advanced Q experts help you (elwesso, q45tech ect.)

I don't know much about the Viper Alarm system, but if it has an engine immobilizer than it it possible that it has something to do with it, but I would think that you would have to do something to trigger it first.

[mexpelon83]

In order to completely rule out the fuel system out you MUST do a fuel pressure check. After that if it still doesn't work than you will need to have the more advanced Q experts help you (elwesso, q45tech ect.)

I don't know much about the Viper Alarm system, but if it has an engine immobilizer than it it possible that it has something to do with it, but I would think that you would have to do something to trigger it first.

Wouldnt unpluging the battery make the alarm go blank?

Well I will do another pressure test. But I am positive that there is nothing wrong with the pressure of the fuel.

[Fridge]

When I was having these kind of problems with my 91 it ended up being the maf. The car would start sometimes and run fine then die and not even try to start just spin spin spin. Remove the plug and clean it really well there are some good products available at the electronics store for this. Also check the cas and clean those connections as well. You can get a inline fuel gauge at harbor freight to make sure you have fuel pressure. but it sounds like control problems to me.