Long cranking
 

I have 90 zr1 whenever i go to start it it takes a good 3 seconds is that normal,any info would be appreciated .

Re: Long cranking
 

perfectly normal.

Re: Long cranking
 

yes, mine too. I believe the ECM controls the slow start. Normal

Re: Long cranking
 

It has to find #1 before it starts

Re: Long cranking
 

My 91 sometime starts the exact moment you turn the key. All depends where compression is at. My Z is modded with cams as well.

Re: Long cranking
 

Thanks guys I feel a lot better

Re: Long cranking
 

Probably not a factor for you but a weaker battery will also cause longer cranking.

Re: Long cranking
 

3 seconds is perfect for both my 90' and 91'.......Now if I could get that quick start for my 1986 Silverado ;)

Brett...what the hay is The ever-popular Ash Tray Relocation to Center Console for Car Wash Quarters mod

Is this another modification I should partake in :D

Re: Long cranking
 

i have a 1990 also. your starting issue is perfectly normal. mine starts the same way every time. My car has no issue, throws no lights at any time.

Re: Long cranking
 

That was a well thought out modification to a repeatable issue....quarters kept falling all over my inner console area. Needed something to put them in. The rubber liner thingy is now in the console I like to think I'm a trend setter.:)

Re: Long cranking
 

I removed the ash tray and just put the quarters in that rubber liner thingy. Did you put something under the flip top lid to hold quarters?

I use quarters LOTS.....carwash and Cappuccino at local Shell Station takes 8 quarters....exactly :cheers:

What I over pay in gas I spend on Cappuccino.....did I just say that nonsense :D

On the start issue of 3 seconds......I prefer a little lag in starting to get some oil pumping at starter rpm before it reves up after started if I have a foot on it.....a better chance to pump up them Chain Tensioners and Lifters that have leaked down ;)

Re: Long cranking
 

The rubber liner thingy is now sitting under the console lid, safe and sound.....full of quarters :mrgreen:

Re: Long cranking
 

Up to 3 seconds on my 90 as well, but tends to be shorter on a hot start. However, I'm in the habit of turning the key ON and listing to the fuel pumps settle before rolling the starter. It, seems to make a difference by maybe a second or so after sitting for a few days.

I read in one of my tech reference manuals that quick starts was one of the goals engineered into the Opti-Spark distributor on the LT1/4 motors. Anywayz, I mention that because that was one of the first things I noticed about my Z was the longer cranking time than my 95 LT1 Vette had. The 95 LT1 with its Opti would reliably fire practically instantly: hot or cold-COLD - it didn't usually matter!

Re: Long cranking
 

I agree. I always let the pumps run prior to starting.

Re: Long cranking
 

Where's Steve here - is this something that's coded into the ECM? Can you explain this a little more in depth?

This is pretty interesting here...

Does Marc's code over-write for hard hot re-starts have anything to do with the 'find #1 before starting' code?

Mine is the first fuel injected car I've ever owned, that didn't start immediately. I usually keep them tuned well, and mine is pretty cleaned up now (32k), and does start marginally faster with Marc's Memory / Calibration Module here...

Re: Long cranking
 

That "rubber liner thingy"? I've had 3 C4s 2
from new and didn't have one? Do the later cars,
91 on, have them? Often wondered what to do with my quarters...

Re: Long cranking
 

My statement is a very abbreviated, It refuses section in the FSM 6E3-A-22 thru 29 and 6E3-A-52 & 53 basically when cranking the ECM must see the Camshaft sensor at #1 before it starts. I could be wrong but that's how I read it.

Re: Long cranking
 

Thanks! You know more than I do here, and I'd sure like to learn more on it...

Looks like book time. Again. Still. Forever... :D

Re: Long cranking
 

I do not know if the Rubber Liner Thingys are stock or not....but.....you can get them on Ebay....but it will cost you 64 quarters :D

Rubber Liner Thingy on Ebay

I kind of like to spin the crankshaft with the starter a bit as the oil circulates just a tad before it revs up.....I forget exactly when the oil pressure starts showing on the gage but I think I recall oil pressure showing a tad when doing a compression test after a few crankshaft revolutions.....

Re: Long cranking
 

Mid America also has them

http://www.mamotorworks.com/Corvette...ction-603188-1

Re: Long cranking
 

Agree ,with the reluctor setup on a DOHC the engine has to find the reference at cam and crank and it probably checks it....


Also an engine were they were worried about cam seizure on cold start up(thanks to a BG employee starting then at full throttle), alittle pre-oiling is probably build in....does not hurt to get the pressure up before it fires.

Re: Long cranking
 

It startles you when it fires instantly upon turning the key, but it does happen from time to time. I always like it better when the engine cranks for a few seconds so it can get oil up top.

Re: Long cranking
 

That's what I'm wondering here now - maybe the coding is written to spin up and get oil pumped, BEFORE ignition to any cylinder - such as #1 :confused:


ed.:
Brett beat me to the punch here; immediate startup, when #1 'fire' happens to be in 'X' position in rotation???

Re: Long cranking
 

I thought there was a four second delay to firing up.

Re: Long cranking
 

Mine also starts instantly when hot, I wonder if it looks at a percentage of oil pressure and temp also. And if it is just before the sensors signal the ECM.

Re: Long cranking
 

Mine generally only does it upon the first start of the day....when it happens, which is only now and then. I generally start the car every day just to keep oil up top.

Re: Long cranking
 

I don't start mine every day, but when I do start it I also let the pumps run a bit before I turn it the rest of the way to crank it. I had to do that on my BBC in my Nova or it would stumble bad when started and sometimes backfire thru the Carb.... So I kinda got used to doing it...:p
Mine cranks for 3 or 4 seconds as well.

Re: Long cranking
 

Speaking of oil pressure at start up, anyone
ever use an Accusump?
Where would you plumb it in?
Where would you put the sump/accumulator?

Re: Long cranking
 

Always nice to feel good.

Dual Oil Filters
 

I would plumb it into the oil filter adapter (maybe oil Cooler Lines).....but would have to check on that for sure first.

I was working on a Billet Aluminum Remote Oil Filter Adapter a while back and had it sized to fit under passenger side headlight (I think I was relocating the coolant overflow). The Design was for Dual Oil Filters. I was working on a System that would NOT Drain Back but still easy to change filters without a mess.

That Remote Oil Filter Adapter I Designed fit in place of the present Oil Filter. Had SS Braided Oil Lines going down to the Billet Aluminum Remote Dual Oil Filter Housing Adapter. Now that I think of it......I think I left the Coolant Overflow in place and positioned the Remote Oil Filter Housing Adapter where my Secondary Pump was previously located (Since Removed).........Or......moved existing Coolant Overflow Tank where Vacuum Pump was located and positioned Billet Dual Oil Filter Housing Adapter in place of Coolant Overflow Tank. I have the specs ;)

Oil Filter Adapter fits on existing Oil Filter Housing
http://i287.photobucket.com/albums/l...2a494b9a4b.jpghttp://i287.photobucket.com/albums/l...005afe1872.jpg

Dual Oil Filter Housing Adapter fits in area under Passenger Headlight
http://i287.photobucket.com/albums/l...79f151ad30.jpghttp://i287.photobucket.com/albums/l...e73a29b14f.jpg

Re: Long cranking
 

I didn't like the original factory start-up procedure because it takes far too many cranks before the engine starts. This is due to the ECM delaying fuel delivery.

When the engine is turning over, the crankshaft sensor sends a pulsed signal to the Ignition Module. Every revolution produces a sync-pulse (odd-pulse). Once the ignition module synchronizes, it sends consecutive signals to the coils and sends a pulse stream to the ECM. When the ECM detects the pulse, it activates the fuel pumps, waits a moment or two, then pulses the injectors.

Due to the failure of component U13 in the ECM, I added a general-purpose-microcontroller and wrote custom firmware which now controls the 8 injectors. On start-up, the new MCU monitors the coolant temperature sensor and engine RPM and when appropriate, hi-jacks the start-up process.

For the first time ever, my ZR1 now starts with the first spark in cold, warm or hot conditions.

Re: Long cranking
 

Hello,

In general, ZR-1s take a few seconds to start. My 93 starts instantly, not even giving the oil pressure time to build up (cold or hot engine). Where do you think this symptom comes from ? Crankshaft sensor failure ?

Thanks for your answers!


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