No start

[fastasleep]

Quoting keydiver:
I've seen quite a few posts from guys who say that the engine floods with so much fuel that it won't start when the coolant sensor is bad/disconnected. The ECU thinks its -40*, so it adds a TON of fuel.



Wait... So, lets say my car doesnt like to reach operating temp and my gas mileage has been horrible... = bad coolant sensor? /ubbthreads/images/graemlins/hsugh.gif

 

Your engine has 2 coolant sensors, one for the ECU and one for the gauge. We've been talking about the one for the ECU, which sticks straight up from the top of the thermostat housing, and often has bad wiring/connections to it. But, if you mean that your temperature gauge in the dash never gets up to full temp, and the ECU's coolant temp agrees that you are too cold, like 160-170*, your thermostat is probably stuck open and you should get a new one, and make sure it is the stock temperature, not a lowered one. If the coolant never reaches 180* the ECU stays in enrichment mode.

 

[BoostedAWD91]

im also running the maft translator, is there anyway to test that to make sure its working w/o a logger? maybe the element got iced over?

 

[BoostedAWD91]

just replaced the coolant sensor and yet it still wont fire. It acts like it wants to fire but it wont. both wires going into the harness are exposed but not torn off so it still should be ok i would think, unless they are shorting each other out when its plugged in. maybe ill try cutting the harness off and running the wires directly to the sensor

 

[SleepinGVR4]

Quoting keydiver:
Make sure it is the stock temperature, not a lowered one. If the coolant never reaches 180* the ECU stays in enrichment mode.



I did not know this. I think I'm gunna get another thermostat.

 

[BoostedAWD91]

replaced the Coolant temp sensor and tried it and still wouldnt start. So for shits and giggles i just cut the harness off and wired in some connectors right to the sensor and after a good amount of cranking it finially started /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/worthy.gif
took it out for a drive to clear everything out and brought it back, was kinda scared to shut it off case it wouldnt start it. Shut it off and started it and did this a few times and it still starts THANK GOD!!!
The only thing that worries me is it still is taking alot of crankin to start

 

[BoostedAWD91]

i dont get why it is so hard to start. Just alittle bit ago it took like 15 seconds of cranking for it to start /ubbthreads/images/graemlins/banghead.gif

 

[toybreaker]

My apologies for some mis-information.

I have consulted the oracle (Jeff /ubbthreads/images/graemlins/worthy.gif ).

It turns out I was incorrect on assuming that the engineers gave us a clear flood mode. /ubbthreads/images/graemlins/blush.gif

It's a bit suprising, because bosch had it in their systems in the seventies... /ubbthreads/images/graemlins/dunno.gif

At any rate, Chris, I'll put a new pigtail for the ecu coolant sensor in the mail tomorrow, and hopefully that will help eliminate that as a source for this problem.

I would spend some time making sure everything else is tip top in the ignition system. I've been seeing a lot of coils with corrosion in the terminals where the plug wires go, so that definately needs to be checked.

An update/pic on the color/condition of the fresh plugs you installed would be helpfull, as they've had a chance to see some combustion cycles, so they'll tell us a little about how you're burning.

It will make advising you on where to go next a little easier, as fuel pressure and many other items on the fuel side can lead to hard starting, and narrowing things down to all cylinders/some cylinders will make the quest to solve your issue much less involved.

P.S. beg/borrow/buy a logger!!!

It'll help a whole bunch. /ubbthreads/images/graemlins/smile.gif

Just watch the parts for sale section, or post a wtb.

This site is an excellent source for procurring stuff from awesome buyers/sellers, so check the good guy/bad guy sections, and buy with confidence from people with good feedback.

I was lucky enough to get a replacement from Robert, (Thadirtybird), for one that was borrowed (and not returned /ubbthreads/images/graemlins/frown.gif ) . He even included the software for the palm, and copies of the various logging programs in the deal.

Can't get much better than that! /ubbthreads/images/graemlins/cool.gif

 

[BoostedAWD91]

ok im not sure whats going on. sometimes the car fires right up and sometimes it will just crank and crank and after like 3 minutes of cranking it finiallt starts. seems like when its cold it starts fairly easy but once its warm it doesnt wanna start. i will go out in the morning and it will fire right up. i will drive into town about 10 minutes so its at operating temp and ill shut it off and when i go to start it again it doesnt wanna start. what could be some causes of this?

 

[Kenny_Kline]

Just start replacing stuff until it starts... I love these threads.

The car will not start when its flooded/gas washed. If you have a spark tester, let car run with it switching each spark plug and watch how it acts. If it wont run, check when cranking. See if its getting spark when you crank. If not, possibly bad crank sensor? You may be getting spark when its running but it may not be consitant. Also, I would check for a hung injector. They also make a tester for that. Test all 4 and watch how they pulse.

Please stop guessing and replacing things and diagnose the issue. Report back when you do the 2 tests above, until then, your just wasting your time and wasting money

 

[BoostedAWD91]

that is the worst advice i have ever heard. the idea is to solve the problem and find out why its happening. why would i blow a bunch of $ replacing parts that are already good? ur not reading what my problem is. if i didnt have spark it wouldnt start. it just takes a while to start . their is no crank sensor, just a cam angle sensor which is brand new

 

[Kenny_Kline]

LOL!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Why would you blow a bunch of money?? You mean why would you blow anymore? Your clearly getting fuel but you went ahead and did the fuel filter hoping it would solve your problem??? I was being sarcastic about you replacing a whole bunch of stuff but doing very close to none diagnostic work. My advice is above. Go diagnose those 2 things and report back. It will help ALOT!!!!

You say it takes a while to start? Well test for spark while cranking and see how strong it is, if any. Its really not that hard dude... it takes more effort replying online than doing the 2 tests. The internet cannot fix your car especially when your not diagnosing things and if you call what you have done diagnosing, you will get nowhere with the car.

I have read your problem and there can be times when cranking, you dont get spark. Also, if your getting spark while cranking and still no start, it could be a hung injector or injectors. Go run some test on your injectors and spark plugs. While your at it, check your base fuel pressure. If you dont come back with those results, your going to make it very difficult for yourself and get no where

 

[BoostedAWD91]

well after getting a nice warm garage to work in i got to dig alittle deeper into diagnosing my problems and did some tests that i wasnt able to do before and the results were the worst anyone would want to see
Compression in order from 1-4
65,50,30,110 /ubbthreads/images/graemlins/bawling.gif
i didnt believe it at 1st so i tried 3 different compression gauges and they all came back with the same results.
Also i was able to hook up a fuel pressure gauge and with the vacuum hose attached at idle it was at 50psi
soo... seeing this is my daily driver and i dont have the $ at the moment to rebuild the engine i dont know what im gonna do. The only thing i can really afford to do is rebuild the head and hope that is most of where im looking compression through bad valve seats

 

[ktmrider]

Hmm, that would explain the hard starting. Did you ever check the timing marks like Toybreaker suggested?
May have skipped some teeth, if so the valves may be bent...

 

Have you tried adding a small amount of oil to each cylinder to see if the compression comes up? I've seen cars that sat for a long time, or ran extremely rich while starting and washed the oil off the cylinder walls, both of which couldn't build enough compression to start until a small amount of oid was added.

 

[BoostedAWD91]

no i ran outta time before i got the chance to try that, but that will be the next step. either way im looking at a rebuild

 

I'm sorry to hear about your luck man.

 

[4nmscle]

do the injectors have a pulse or constant?

 

[FlyingEagle]

Duty cycled, or PWM (pulse width modulated). It looks like a square wave graph, with the top being "ON", and the bottom, "OFF". The more time spent on the higher the duty cycle, and vice versa.

 

car should start fine with the compression readings that you posted.. you shouldve added a teaspoon of oil to each cyliner when testing to confirm the they were really bad... also it seems that the problem is really a hot start issue wich most likely is a coolant temperature sensor problem