DsmWisemen please help!

[dsmspyder97]

Okay, i put a previous post, thought i had asoltution and i was wrong.
90 eclipse Gsx 150k
Completely stock
Optima red top
New alternator
All new fuses
Karking rebuilt motor w/500mi
Rebuilt turbo

Okay origianlly for the initial 500mi i had no problems except for the altenator which i replaced. Was very simple. Only mild problem i had was when i was at idle for longer then 30-40 sec my vacuum would pull to 0 and as it began to fall back to -7 my rpn would shoot to 1500-2000 range. Very annoying especially when i was in the drvive thru So i figured the Idle control solenoid was going bad. I had already purchased a parts car but was awaiting picking it up. Well about a week ago i park the car with no problems, come back out a few minutes later and the car just cranks. Pulled plugs, no spark. So i went and bought new plugs and wires. When i came back i tried starting again and i hard spark and the car turned on. Idled for 3 minutes then shut off. Well i hadnt installed the new plugs and wires so i figured maybe ecu,coils, or igniter. Well I picked up my parts car over the weekend, swapped the ecu and it started fine. Drove it for 2miles then parked. Same problem again, so i pulled the coils and igniter from good running parts car and put them on the gsx. I got a little spark, then it went away. Im thinking that this is a ground problem. Although I searched all the grounds and they all appear to be on. I have troubleshot this to death. The parts car is same year same model, motor just had low compression in cylinder #3. Only wiring issue i can see is a black wire with white stripe on back of intake manifold is exposed. It actually goes into a pin on a plug on the back of the manifold, then runs to firewall. I electrical taped it and still nothing. I have no check engine light, do i possibley have a bad sensor that is sending too much voltage to my ecu and frying it ??? I opened the ecu and saw no problems with the capacitors. Or am i not getting spark from some kind of grounding issue that i canno locate. I just need help. If im not getting ground for spark, would i still have ground for my fuel pump to pulse, because i do have fuel. Is there anything else i can check that would not work if im having a grounding issue, so i can rule other things out?????


Thanks in advance

DsmWisemen

 

[GTM]

okay, update from last night.
...
Also I think i have the wrong ampage fuse for my alternator im running a 80a, is that correct? Or should it be higher like a 100 or 120? I checked all plug connections and all were tight and secure throughout the engine bay.
...

Once again thanks to all, looking forward to getting my daily d back on the road, it looks kinda sad setting next to my project and parts dsm's

Argh I can't keep score of who said what.
AND
I don't know how many people are giving you advice on and off this thread.
.........................

I will make the following:

You should be using either a 100amp if turbo or 2.4L, and 120amp if 2.0L _non_ turbo fuse.

You need to check _all_ 4 of the White fusable links that according to my schematic are attached to the positive battery post.
.............

Does the engine crank?
Did the radio work before these problems started?

Cheers,
GTM

 

[dsmspyder97]

engine cranks with no spark, and radio never turned on even though i replaced the fuse before i had these problems, though the radio never powered on even though i changed that fuse, so from the beginnning it never powered on.

 

[GTM]

engine cranks with no spark, and radio never turned on even though i replaced the fuse before i had these problems, though the radio never powered on even though i changed that fuse, so from the beginnning it never powered on.

Okay, we can dismiss the radio as being a clue. And we can also conclude that one of the fueable links to the Ign Switch is good.

Still need to know about the other 3 links.

When the key is ON does the key light come on? Does it turn off after 10 minutes or never turn off?

You have swapped out just about everything so either you have a wire, fuse or ecu problem that we need to find.

Cheers,
GTM

 

[dsmspyder97]

**Big Breakthrough** Okay i have a friend who thought that his ecu was blown, so i took my ecu to him. First i opened his and saw that the capacitors had leaked out everywhere which made me feel way better about how mine look. So i tried my ecu in his car.....RESULTS...

#1 The CEL light did come on when the key was in the ignition
#2 The boost gauge did go to 0 vacuum when key was in ignition
#3 WE GOT SPARK WHEN WE WERE CRANKING

Im actually really happy to find out these 3 things. I'm gonna rule out my ecu being bad unless anyone still thinks it is. Also with this new evidence im thinking that it's definitely a sensor or ground that im not finding.

Happy to almost have my car running again, please help me wrap this problem up with any additional info.

 

[WFORACING]

It still sounds like it could be a crank sensor or wire to the sensor to me... I have had a few experiences with them and they can play games like these....I would check it out .....Hope it helps

 

[dsmspyder97]

just got done tearin apart my parts car, no luck it appears that the sensor was taken by the previous owner.......((Crank angle sensor))

 

[GTM]

just got done tearin apart my parts car, no luck it appears that the sensor was taken by the previous owner.......((Crank angle sensor))

Have you checked your current Cas with a DVOM? Should show continuity, I've not looked for exact ohm readings yet.

If it's an open circuit you could pop in in the freezer for 1/2 hour and recheck. If it appears good you can try a hair dryer and see if it gets an open circuit.

Cheers,
GTM

 

[GTM]

just got done tearin apart my parts car, no luck it appears that the sensor was taken by the previous owner.......((Crank angle sensor))

Are we talking about a 1990 or a 1997 car???

I've been giving information for your '97... crapola!

To the best of my knowledge you do not have a CRANK ANGLE SENSOR, you have a CAM Angle Sensor. These are known to fail. If you have a repair manual it will tell you how to test the CAS. My electrical schematic is pretty poor but I can dig through it.

I still have a question about the Alternator you upgraded, does it have 2 wires or 4 wires besides the B+ on the back of the housing?????????????? If it's the 4 wire and you are using it in the '90 then you have 2 wires not connected.

If you do pull the CAS off make sure you observe where the V notch is located because it's possible to install 180 degrees out and the car will try to start but _will not_.

You will still have the 4 fusable links which have to supply power to some of the critical relays beside just the key switch.

My humble apologies if I've sent you looking for wrong colors and connections. damn damn damn

Cheers,
GTM

 

[dsmspyder97]

Okay, so like i previously posted i was looking for a 'Crank Angle Sensor' on my parts car. First let me see if iu can get this cleared up. Accordin to my Chiltons manual, on my 90 I have a 'cam angle sensor' which supposedly supplies the reading for the fuel pulse. Then it gives me a diagram and shows me location of the 'Crank Angle Sensor' which it tells me that supplies the signal for spark. So since i changed out the cam angle sensor i still have the fuel pulse (( i checked that over the weekend)) and i am still without a spark on any wire. I'll check on the altenator wire during lunch today GTM and report my findings. I'll also look on my GSX for the plug and 'Crank angle sensor', maybe somethings loose. I was excited when i found out my ecu was good on a different car, and it was supplying spark and powering up. Now im just getting frustrated. =-/

 

[GTM]

Okay, so like i previously posted i was looking for a 'Crank Angle Sensor' on my parts car. First let me see if iu can get this cleared up. Accordin to my Chiltons manual, on my 90 I have a 'cam angle sensor' which supposedly supplies the reading for the fuel pulse. Then it gives me a diagram and shows me location of the 'Crank Angle Sensor' which it tells me that supplies the signal for spark. So since i changed out the cam angle sensor i still have the fuel pulse (( i checked that over the weekend)) and i am still without a spark on any wire. I'll check on the altenator wire during lunch today GTM and report my findings. I'll also look on my GSX for the plug and 'Crank angle sensor', maybe somethings loose. I was excited when i found out my ecu was good on a different car, and it was supplying spark and powering up. Now im just getting frustrated. =-/

I really need to get up to speed here. To the best of my knowledge a 1990 DOHC DSM does _NOT_ have any crank angle sensor!!!!!

It does have a CAS which is CAM ANGLE SENSOR and is bolted on the head and driven by the intake cam with a dog (blade) drive and will look similar to this and a matching slot in the cam --O--. It will have a small V stamped into the circle which must match the position for 1 cylr when and the valve timing is set correctly

To my knowledge there is no relationship between this and the fuel pump nor does the fuel pump "pulse".

In the crank mode the fuel pump relay is activated and the pump will run, when the key is released the pump will not run UNLESS the engine has started.

With the key on and holding the cas in your hand you should be able to turn the blade drive and produce spark... no _if and buts_ about it. This is a must or you have a bad CAS or a bad circuit to or from the ECU.

These are absolutes unless I'm loosing my marbles. You may find pictures and more info on Vfaq.com.

Cheers,
GTM

 

[dsmspyder97]

Car turned over 4 times last night, it idled like crap, i thinkim off on my cam angle sensor install. All i did was go and clean every single connection.......again. I still dont think its completely fixed. This might just be a temp fix

 

[toybreaker]

I really need to get up to speed here. To the best of my knowledge a 1990 DOHC DSM does _NOT_ have any crank angle sensor!!!!!GTM

Those wiley engineers have co-located a tdc sensor in the cas housing.

Calling it a crank sensor is a bit of a stretch, , but, none the less it's in there.

I *believe* it's an optical trigger ring on 90-91 cars (greentop), and I think it's probably very similiar to what you saw on nissans back in the day, Gtm, but I dunno...I'll blow one up in the name of science and get back to you tonight.

I do know the 90 cars have a pigtail/short harness section. It runs from the housing over to the firewall and plugs into the main harness there. I've seen a bunch of "creative" wire routings that put the cas harness against different items, causing chafing/wiring insulation trauma. In addition, the cas harness makes a sharp bend, right where it leaves the cas housing. Heat, oil and repetitive flexing can cause the wires to fatigue there. The results can be something similiar to what you got going on. A visual inspection may pay great divedends.

It sounds like vforacing and I have had similiar experiences in this regard..nice post,btw..

There's about a kerbillion little cracks in the insulation on a lot of cas's that have seen high temps, and the breaks in the insulation concentrate the flexing on the wire strands in just a few spots. The individual strands of wire will break, one by one untill continuity is lost. The really weird part is flexing the wires around during the installation/removal can give/break continuity at random times....

It's enough to make a man...walk....to drink....

I had another thought on the ecu situation as well.

Did the other car ACTUALLY run on your ecu? You stated it had spark, but I didn't understand if it ran or not.

Used e-prom ecu's for these cars can be a bit of a pig-in-a-poke proposition....until a car actually runs/idles/drives I don't consider the brain transplant a success. Especially on the 90 model year cars..they stand alone as far as the interchange goes...and, they're abby-normal enough without adding another variable to the mix

I've been seeing a bunch of e-prom ecu's that have been "improved/chipped/modded" recently. It's possible your ecu is a chipped e-prom compensated for 750cc injectors, or some such nonsense...everybodies a "tuner" now-a-days...

A quicky visual inspection will tell the tale. If it is a factory e-prom, the chip will still be soldered to the board and will have a calibration number on it...otherwise,..all bets are off.

Just a thought,...

good luck!!

 

[dsmspyder97]

Thanks on the food for thought, the ecu that works i cant get the plate off.......even with a drill, and using the hit the screwdriver with a hammer method. Yikes

 

[toybreaker]

There's about a kerbillion people in on this thread, and it's starting to get confusing to follow.

One clarification... not all 90 ecu's are eproms. Please check out tmo's website for more information. Sorry, can't do the link thing,... I'm a computer tard..

The ecu case screws are really hard to get out. I've found the best way is with a tightly fitting slot blade screw driver. Try really hard to not cheese the screw head. If it does happen, just use vise grips on the screw head BEFORE it looks like the dog has chewed on it...

***Never hit the board screws with any force, the board is VERY delicate.*****

Also, you don't need to remove the ecu board from the case to determine if the e-prom chip is a virgin. My most humble apologies, I should have been more specific. If you look at the e-prom chip from the top, where it goes into the board, it's little pins are soldered right into the board...(virgin) or the chip is sitting on a little spacer ~1/8 high...and is removeable...and quite likely no longer stock..(put away the prybar.. ...we don't want to take it out).

Most of the reputable chip guys put a sticker or some writing inside the case, detailing the particular programing and injector corrections etc. contained in their e-prom chip. (That still doesn't mean it's the same chip, people like to play with these cars, and there's been a bunch of times that the ecu sticker and calibration aren't even in the same ballpark)

I must also say that even an improperly calibrated ecu will give spark, so upon further reflection, my advice wasn't all that helpfull in that regard. I've seen a few cars not start/run terribly from a mismatch where the ecu expected huge injectors, and didn't supply enough fuel, but that's probably not your problem. My most humble apologies for running you down a dirt road...

Anyway, a quicky visual inspection will tell the tale. Please post back with the results, and perhaps the board/chip numbers so one of the wiseman can tell you what you've got.

A quick word of caution, ecu's are fairly fragile, please no touchy the board. Static electricity and the oil from your fingers is bad for the sensitive goodies that make the thing work. Please go to tmo's website and read their info., it's first rate, and there's some really good pictures.

One last thought,

I went to test a few 90 cas's and ignition coils, to see if I could gain some insight into your problem, and develop a few easy tests. I was using my 90 gsx, (which I just drove 90 miles.) I put the first set in and NO START....hmmm...bunk parts.. Put in another cas, nothing, coil pack, nothing...errrrr.. Put in the set that I just drove 90 miles on...still no start...no fuel and no spark...

WTF

A carefull visual inspection of the cas harness connector on the firewall revealed the female pins were spread open a little, and the little tangs on the cas harness plug weren't getting good contact. A little CAREFULL work with a 90* pick got things straightened out. There was a little corrosion on the pins that I took care of with a spray contact enhancer I got from radio shack.The car lit right back up... And I proceeded to check the other cas's and coils.

Which, of course, worked...

At least I've got some known good parts for inventory/test by substitution

Freakin cars, I should have listened to my mother, she wanted me to be a doctor

 

[dsmspyder97]

Im going to attempt to re-install my CAS correctly at TDC I'll let ou guys know what happens. Crossin my fingers

 

[billyt]

Well... did it start? I spent good time reading this thread and it left me wondering what happened? I'm in a similar situation and would like to know in order to solve my problem.

 

[LandSpeed-DSM]

This thread is 6 years old

 

[99ECLIPSEGSXDSM]

What all have to replaced/checked?