car ran fine last year sprayed motor off next day carwould not start everyone said opti. car sat all winter put in new battery ran the test from the sticky and everything tested fine. swapted my MAF with the one from wife tahoe the car started right up ran like a dream. next day wouldnt start again Pulled #1 plug and cranked the motor over very intermintent spark. i am at a complete loss and just want to start slinging parts at it just to find out that is the prolblem any suggestions or test will help. there are no codes either.

 

When you say it won't start, what exactly is happening when you try to start it? What all have you done to the car? You should add a "signature" to better help you.

 

Here's what I'm gathering.

You HOSED the motor down to wash it and now it starts intermittently.

Intermittent spark tells me you've got opti problems - pretty common after hosing off an LT1. There's DOZENS of "washed motor now problems" threads out there.

 

to answer both of you. car is a lt4 383 with a list of mods i have read all the other post about washing off the motor and did all tests from the sticky on the top of the page and opti tested just fine i just have a very weak spark tune is fine plugs are good along with wires if i crank on it for awhile it will eventuly start but runs like crap in high rpms. if you all think it is still my opti should i replace the whole thing or just cap and rotor

 

Take the Opti off, and very carefully take it apart so you can look at the optical pick up and disk. At the very least there's water in it, and the worst case is its rusted or corroded form sitting all winter with water in it. I'm guessing water splashing around in it is causing the intermittent starting, and testing fine.

 

thats the odd part when i spayed the the motor i had very little water press and i only sprayed the valve covers off will look into though i have had blower on it for past 2 weeks thinking the same thing that water might be inside there just might have to bit the bullet and shell out the cash for a new one AC Delco is not cheap

 

There is the possibility that water has seeped into a connector as well. Something to keep in mind.

 

If you got water in the opti that easily then it was not assembled right. Certainly possible but not an "opti problem" more of an operator problem. I have pressure washed LT1s and never killed an opti and sprayed everything. If a vented one is assembled right and the weatherpak connector is in good shape they do not get water inside, and if they do they just need to dry out like any other distributor.

 

In cold weather with them not running they will not dry on there own.....I've seen this happen with condensation over a winter while in storage.

 

96capricemgr what do you mean opperator problem opti was put on when motor was built about 5 years ago and was a new unit and it is vented i dont see how it could be the opyi but what else is there have been trying to dry it out have a blower motor from a furnace pushing air if you are trying to critize people how about giving some advice if you think you know anything that might help

 

If water some how got in and stayed there while sitting, it might have corrosion. You should check the opti connection and see how it looks. It might be worth removing it, if the problem persists. If I had some extra money lying around, I would get a new one and swap them out and then you have a spare if it is something else. Lot of money, but letting the car sit longer with no clue isn't working either. The money spent having a mechanic look at it is only going to be expensive and they usually just throw parts at it anyways. Is the battery fully charged? If you replace I would get the AC Delco complete unit.

 

I think you have to understand that an opti is a distributor with a replaceable cap and rotor. These items, the cap and rotor, are wear items...just like on a 'normal' distributor. Anyway, over time, the plastic these things are made from degrades and give problems, especially if wet out with water and soap or coolant. Some optis seem to go forever, some don't. Anyway, the data provided is that the car started to act up after washing and some have suggested that's the problem. Dwayne suggested that a properly assembled opti is well sealed and should be able to withstand being washed. Unless you disassembled the opti while installing it on the engine, that operator problem lies with someone else.

In any case, pull the four wire connector at the opti and inspect for corrosion. Spray the opti with WD-40 or CRC 5-56 to dry it out. Spray the wires, too. If the problem goes away, think about replacing the cap, rotor and wires at a minimum. I'd replace the entire opti while in there but that's me....

Good luck!

 

Take it off and have a look at it. If its not rusted, I've cleaned them and dried them and cleaned the optical pickup off with a Q-tip and rubbing alcohol and they are still going with 7G shifts with NO break down. Put a new MSD cap and rotor as they are the wear parts.

The tubes for the vented Opti are routed by the valve covers to the intake on the drivers side. That could be how the water got in the Opti??? Check the small hoses for cracks or breaks. Good luck.

 

Be careful with the alcohol and electronics. Over time, alcohol can develop crystals that can be conductive and cause issues. I would look into using a mild contact cleaner(make sure it will not dissolve plastic...some will).

I've seen where contacts were cleaned with alcohol, then 2 or 3 days later, the entire area is white with crystals growing on it. They can be conductive too.

 

I'm not discounting your observations but there is nothing in alcohol that forms crystals. The residue you see must have been from a contaminant..like the Q-tip or the container..and not the alcohol itself.

If one uses alcohol, the stuff to use is Anhydrous Isopropanol. There is no water associated with this version. You can find it in the drug stores where diabetics get their supplies.

Rubbing alcohol has up to 30% water in it and takes longer to dry....and more time to leach junk off the surreounding areas.