Spark,Fuel,No Start-Update:Car is running!

Bluntz

Registered User
ok people, i have 2 other threads going that i thought were accurate but they are not. When i ultimately figure this all out i will add solutions to all threads....
PLEASE HELP ME PEOPLE!!!
I just dont know what else to do. I have went up and down trying to diagnose and fix this issue. The car used to run but only run really rough. Now it wont even start. Here is what i have done so far.
Changed oil and filter. Oil looked fine with the exception it was really black and had a faint odor of fuel. 5 and a half qts came out.
Changed relay in trunk to keep the fuel pump from staying on continuous after car is turned off.
When i try to start it it wants to start but wont, if i hold the pedal to floor and try it nothing. If i try it regular and give it gas as im turning it over it will backfire.
I put a brand new DIS module in. I have NO upshift light when i start, tach is fine. i have spark, i ruled out cam crank and dis.
I have one code coolant temperature sensor. they are 14 bucks im gonna put one on in a couple hours. Other than that no codes.
I took air hose off and sprayed starting fluid in there and still nothing.
I got under car and visually inspected the Hamromnic Balance as best i could, no cracks and the bolt is fine.
There is only 2 things i can think of, one i can do right now, Spark plugs, spraying the starting f;luid in there and it not starting even though i got spark at the coil dont make sense to me, it HAS to be fouled out plugs no????
Im gonna go get new plugs here in a few minutes.beyond that my most impostant question is what relays can go bad and cause the car to not start?
Would it stand to reason though that if the relay went out it would prevent ANY spark from reaching the coil right or wrong? Im just trying to theorize these issues out in my head and i am going crazy. Im getting so frustrated but i am not willing to quit yet.
I got the car 3 weeks ago, it never ran well always rough smelled of strong gas and what not, but it always started. Now it wont even do that.
Im sorry for the lenghty post gentleman but if you could point me in the right direction id appreciate it.
 
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ok people, i have 2 other threads going that i thought were accurate but they are not. When i ultimately figure this all out i will add solutions to all threads....
PLEASE HELP ME PEOPLE!!!
I just dont know what else to do. I have went up and down trying to diagnose and fix this issue. The car used to run but only run really rough. Now it wont even start. Here is what i have done so far.
Changed oil and filter. Oil looked fine with the exception it was really black and had a faint odor of fuel. 5 and a half qts came out.
Changed relay in trunk to keep the fuel pump from staying on continuous after car is turned off.
When i try to start it it wants to start but wont, if i hold the pedal to floor and try it nothing. If i try it regular and give it gas as im turning it over it will backfire.
I put a brand new DIS module in. I have NO upshift light when i start, tach is fine. i have spark, i ruled out cam crank and dis.
I have one code coolant temperature sensor. they are 14 bucks im gonna put one on in a couple hours. Other than that no codes.
I took air hose off and sprayed starting fluid in there and still nothing.
I got under car and visually inspected the Hamromnic Balance as best i could, no cracks and the bolt is fine.
There is only 2 things i can think of, one i can do right now, Spark plugs, spraying the starting f;luid in there and it not starting even though i got spark at the coil dont make sense to me, it HAS to be fouled out plugs no????
Im gonna go get new plugs here in a few minutes.beyond that my most impostant question is what relays can go bad and cause the car to not start?
Would it stand to reason though that if the relay went out it would prevent ANY spark from reaching the coil right or wrong? Im just trying to theorize these issues out in my head and i am going crazy. Im getting so frustrated but i am not willing to quit yet.
I got the car 3 weeks ago, it never ran well always rough smelled of strong gas and what not, but it always started. Now it wont even do that.
Im sorry for the lenghty post gentleman but if you could point me in the right direction id appreciate it.


i dont see anything about bad gas?

i went round and round with a car i was working on every time i pulled the plugs they were soaked in fuel had fuel pressure. has spark and good compression. i would kind of lean to bad gas. has the car sat a long time?
 
The car sat all winter with the previous owner thinking it was a head gasket.
It has been empty since i have owned it, ive driven it approx 50 miles since i had it, 50 rough miles though. Last week i put 2 gallons of 93 in. Fuel is definately good.
 
Check fuel pressure.....

Sounds like you might have a crimped fuel return line....

That would explain the extra "oil" in the oil pan....

Or a bad fuel regulator....
 
Thank you i will get a fuel pressure tester and try as soon as i can, i did spray starting fluid in there though and it didnt start, that dont rule out some fuel issues?
 
What year is your SC.....

I have a 90 that the PO changed the fuel filter on, along with some other things....:rolleyes:

When he finished the install, he got the return fuel line caught under the hose clamp that holds the filter in place....

No fuel was returning to the tank and fuel pressure was over 90 psi....

Pulled the dip stick to check oil and it was 2 quarts over....

Replaced fuel return line and she is running fine.....:D
 
im gonna be pulling plugs and putting new coolant sensor on in a few minutes, i will post back pics and results of my efforts.
 
My wife works with the guy i bought this 90 sc from, she was informing him of my problems and let him know i was changing plugs today, he calls me up and tells me not to, he said there is less than 100 miles on the plugs that are in it now, i go on to explain he was wrong in the head gasket assumption, the hg is fine, i also let him know i have spark, fuel, i changed the dis mod, crank cam are good, coil is new, i said the only thing blocking the car from starting HAS to be the plugs or a relay i am missing. He goes on to say, well when i did change the plugs the car started getting worse and worse. I said why did you decide to change the plugs in the first place? He says he thought it was missing at certain times even though overall it ran great, i asked him if he gapped the plugs he didnt know.
I have some hope, if this car starts and runs good today i will dance a jigg for you guys and post it on you tube.

On a downside he dais it took him 4 and a half hours to change the plugs and wires. Oyyyyyy, lets hope underneath is quicker.
 
Once you do get the car running right keep checking the oil. Black oil and the smell of gas after only 500-1000 miles usually means blowby which is caused by worn piston rings. Just wanted to give you that heads up. Can't be sure until it starts running normal
 
So far so good, i FULLY anticipate this car to start.

Put the new coolant sensor in and for ~~~~z and gigglez tried to start it and she backfired immediately which made me happy as it had never done that on opening start before.

The older plugs are SOAKED in either fuel or oil or both. Im very excited and have newfound angst to keep going, this is long job though and now i am forced to get under car outside in a dirt driveway, i am a big guy about 300 lbs 6'5, i do not like being under vehicles. However you gotta do what you gotta do and i am headed off to go jack my car up and secure it strong.

1 last note, so far these plugs i have taken out are gapped at .048, from what i have read the specifications are for a 1990 3.8 supercharge is .054 gap. Can someone confirm if this is good gap for me to run?
 
That plug gap should be fine on a stock SC - most of us on here usually gap them a little tighter than OE specs. I usually install 103 plugs gapped at .40 and call it a day.

-Tim
 
Well, 5 of the 6 plugs were so fouled it wasnt hard to believe they werent firing, #6 plug when i went to change it was a breeze, so much a breeze the plug wire was already off and i was able to remove the plug with my fingers.
When i seen this i knew i hit paydirt and she was gonna start.....

Jack down, 6 new plugs i get in and BAM she starts right up beautifully.

Thx for all the efforts gentz.
 
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