Help! start.no start??

[looney1316]

just took my 1990 6 sp. to the shop when the owner tryed to start it it turned over but didn't start.i went over with my key and it started right up turned it off and tryed again,no start with my key.sprayed starter juice and it started turnany ideased it off try again no start,wait alittle it started any ideas.vats,computer,fuel system,any ideas before we start looking for grelims under the hood thanks for your help:bash

 

[Baldie88]

I'm certainly no expert but if it is turning over and not starting then I would suspect a fuel problem. The VATS will prevent it from even turning over if that was the problem. I had a similar problem but mine wouldn't even turn over. Start one time and not the next. Found out the starter was binding when hot. Seems to be a fairly common problem with C4s. Replaced the starter and no problem since.

I know it's frustrating but I'm sure someone will come along with some help.

Good luck.

Ron
"Baldie88"

 

[kevi h]

i just bought a 1984 basket case i got it stared once but now a security lite is on and it wont turn over .is there a way of disarming this mode

 

[bill5674]

ok first , vats will prevent engine from cranking.if cranking then lets assume vats is good. check fuel pressure on the rail...passenger side.check w/engine off key on ,i belive its around 40lbs or so...if you have fuel pressure ,you could check ohms at the injectors.do a search forget the numbers.check spark while someone cranks the engine over.let us know what you find.........

 

[looney1316]

if i let it sit about 20 min it starts ,turn it off and try to start it right back up nothing but cranking, let it sit again it starts/ off quick and try to start only cranking when it starts it runs and drives find ???????

 

[John Robinson]

Check the fuel pump pressure

 

[bill5674]

see above........possible leaking injector,check other things first

 

[looney1316]

1st off thanks for all the help/here is the latest thing i found,if car is cold(sat over night)i can start it and turn it off and start it again over and over.i did this drill 3 times today so it seems like a warm motor problem,anyone have any new ideas on that.. thanks again it just shows how helpful vet guys are

 

[looney1316]

thanks

 

[bill5674]

okay..now when you get a no start check the spark.coil or the module could be going bad.most of the oil and wax parts houses sell something that goes in between the plug and wire or the wire and cap. try that and then let us know.

 

[looney1316]

spark is good injectors good we are leaning towards ecm, looking for replacement

 

[looney1316]

if ecm is going bad could that be a reason my mpg's are droping(11 down to 6.5)and it is starting to feel down on power

 

[sstearns2]

i just bought a 1984 basket case i got it stared once but now a security lite is on and it wont turn over .is there a way of disarming this mode

I'm not sure if the 84s have vats. You have it if you have the little chip imbedded in the key. You can take the key to the dealer and they can test it and tell you which chip you have and then you can get a bypass kit from ecklers.

Scott

 

[John Robinson]

Do not get boxed into thinking the ECM is the only control for fuel. The TPS (Throttle Position Sensor) tells the ECM how much fuel to meter based on the opening of the butterfly in the throttle body. You can look in the search engine for information on how to test the TPS.

 

[wrenchmantee]

I went through the same crapp with my VATS system....It got so bad at one point that I started looking into bypassing the entire VATS system. After compiling all the info I could, this is what it took to "DELETE" that damn thing...#1 the key pelet bypass is useless! I sent off for a new memcal prom for the ECM. "TBI Chips" can delete the VATS program that shuts down the injector pulse & the fuel pump. Then I bypassed the starter interupter relay under the column, that took care of the no crank problem. Then you can remove the bulb from the display(Security)...NO MORE PROBLEMS EVER! Cost for parts was $100.00 for the chip and just 1 butt connector....took about 1 hour to do it all.

 

[looney1316]

replaced the ecm it was as good a place as any to start,didn't fix it, any ideas what to try next,a vett is no fun if it is sitting in the garage

 

[bill5674]

throwing parts at it can get expensive.you said the injectors are good,how were they checked?same thing with ignition please tell me how it was checked.during a no start you saw a nice spark at the plugs?not trying to be a d*ck but need some facts so we can help.and please unless im` mistakin vats will cause a no crank,not a no run ..get back to us soon...good luck........bill

 

[looney1316]

switched ecm,didn't help,now what, a vette is no fun if it just sits in the garage

 

[looney1316]

had a mech. check spark with a light between cap and wire.was playing around with alot of other stuff checked injectors with a meter he said something about the readings not being all the same but said none looked bad .you are not being a richard,thanks for helping because as you can tell i do not know jack about this computer crap.test were done during a no start,his guest was ecm or bad ground he was nice enough to check it for free out side his shop but did not have time to take it in and give it a good look over

 

[bill5674]

And i thought about using the term Richard,but not sure if you would have caught my drift.funny. .in the tech section there is a good write up about a no start on a think an89.teaching my self these computer vehicles have a bunch of them in our trucks and machines.ya just have to understand how it works then figure out what is going wrong. did you say it will start with a bit of smelling salts?that would point to a fuel problem.i had an intermitnt hot start on my 90.there was so much corrosion in there that i just swapped it out for a reman unit..car hasn`t ran that good in years ,very smooth idle.....keep us posted