The 90 FSM has the exact same sentence. Makes indeed no sense.

What it leads to, the pick up coil, I experienced, when it's the cause, you won't get any rpms on your digi dash.

I measured a few of these coils, all came up with about 700-800 ohms.

Do you got spark?

I would first make a resistance check of the fuel injectors and a fuel pressure test.

Very interested! If you ship to Germany let me have your PayPal account.

Maybe the temp sensor, indicating arctic temps?

I'll take it!
I currently have a buddy of mine in the area. I can send him over to pick it up and pay cash.

Glad I didn't get a blank screen and my answers weren't lost when I got this:

Invalid submission. You could have exceeded session time. Please re-submit or make a backup of your post and login to resubmit if necessary.

I just took out my explanations how I got there, more fun for all this way.

Ok, I'll give it a shot.

1. left, in left hand drive countries

2. 12

3. 1 hour

4. E V A L U A T E

5. 36

6. 4 L shaped lots with 4 squares each

7. top ball and both outside bottom line balls

8. no idea

9. 7 sheep

10. 5th row from bottom and 2nd to last

11. glass #2

where is 12?

13. B

14. 6

15. C

I killed a Craftsman 8mm socket, as well as an 8mm Gedore which is considered one of 3 or 4 of Germany best brands.
Ended up using a no name 6 point 8mm box wrench and a large hammer.
Try this, won't get much better:
http://www.craftsman.com/craftsman-8m ... ombination/p-00942865000P

Did the engine ever stall while having the code?

Sounds like a good deal to me.

Try the 90 ECM with the 90 Chip.
Once I had a chip that didn't burn right and I got a code 41.
With a stock chip the 383 should run richer. For a start and short idle action you should be safe.

Do you still got code 41?
I'd take a look at the fuses, especially ECM and CCM. No juice no joy.
If it's not a known good ECM, try your other ECM. You know how easy the swap is.
Good luck.

I am pretty certain you just have a different chip in your 383, which is removable. Loosen the 3 10mm nuts holding the ECM in the bracket and turn it around. You'll see a cover held by 4x 1/4° screws. Underneath that cover is the memcal/chip, that you just swap over and you are ready to try with the ECM you already have.

It's most likely an easy fix for you and your L98.
99% your ECM is toast. Since your 90 and 91 use the same ECM, just switch it over and most likely the code is gone and culprit found.

You're on the right track, pull codes! Short upper right corner to lower left corner on the ALDL connector.

Probably end up with a code 41 or ERR. If that happens, take the ECM from your 90, switch the memcal/chip and try again.

So that you know how to use the MV
https://www.youtube.com/watch?v=cRoYbDDGHTk

The pliers-drawer somehow scares me. Reminds me of some bad movies with people in basements tied to chairs not willing to talk
If I am not mistaken, Matthew spends an awful lot of time in the basement .
Anyone seen his neighbor lately, the one with the hanging tree

It got worse over a period of time. First occasionally the light with no effect at all, than some performance loss and rough idle.
Using it as a daily driver it took about 2 weeks until it shut down the engine by itself for the first time.

No such thing as a cam sensor on an L98.
A few times I came across a code 41, was always the ECM.

I don't see a reason, why this VSS shouldn't work.
http://www.ebay.com/sch/i.html?_from= ... ACDelco+213-198+&_sacat=0

It is listed for 91-95 with manual transmission.
Looking at the chip data, both 90 and 91 have 4006.96 pulses per mile.
Maybe there is a connector issue, but if it was me, I'd try it.

As a matter of fact, I used exactly this VSS I have as a spare to test a 91 auto with VSS issues and it did show movement at the LCD display using an electric drill.

The hard to find 213-210 is for Vettes up to 1989, as far as I know. 90 has the ECM, CCM and cluster just like the 91 and following years.
http://www.amazon.com/Delco-213-210-S ... -New/dp/images/B006E0BW7A

I can use a 90 chip in my 91 without any issues. Still don't get, why the VSS should be different?

Just thinking out loud. I hope it helps.
Axel

Ìf the TPS is installed like pictured, you've got a wrong set up! Zhe TPS link is currently above the hook but it belongs below.

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What's the model year?
L98 I would think ECM, LT1 rather defective Opti-Spark, unless you got a weak battery.

Pull off the O2 sensor, or rather disconnect it. Let it run and see if it runs better without it. If it does, the new O2 is toast right out of the box or the ECM is doing BS.

Of the probably 15-20 dead or lazy O2 sensors in various Vettes and F-bodies I replaced, close to none had visible signs.
Maybe my first post wasn't clear. The O2 sensor should at all times be in the 50-950mV range and switching fast back and forth across the 450mV cross count threshold.
Only during warm up, at WOT and during fuel cut off it will be linear and not add to the cross counts.
Idle was always most affected, when the O2 sensor was on it's way out.
I am still pretty certain, replacing the O2 will cure the condition. We'll find out soon, I guess.

The mV should be in the 50-950mV range, and the cross counts a lot higher.
Sounds very much like a lazy O2 sensor. Replace it and the idle situation should be gone.

Quote:
Try replacing those 4 caps with the silver top anyway. I had luck doing so.

Been there, been here....still need the t-shirt

Hi guys,
got the following problem with this animal. It got an 7730 ECM, basically the same like the 90-91 C4 ECM just different connectors.
When we depress the throttle the MAP value goes up for a split second and than drops from like 60 kpa at idle to 40 kpa at steady 2000 rpm.

Looking at my own 91 the kpa's go up when I hit throttle, from idle at 30 kpa to something like 50-60 kpa.

Seems like the values are reversed. How can that be???

We measured all wires from the ECM to the sensor. The ground wires from the CTS and MAP were at the wrong spot. Switched those but no difference.

This is an aftermarket set up from Arizona Speed and Marine.

Any ideas how we can get the MAP values in line?

Right now the engine starves gas, when accelerating.

Could it make a difference just reversing the ground wire and the 5 volt reference signal?
It says in the service manual the 3rd wire being the signal, should read 1.6 volts, unfortunately we don't get that, whatever we tried.

We tried 3 ECMS and 2 known good MAP sensors.

Help guys???

Thanks,
Axel

or this:

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Quote:

Sure, one into the EGR valve and the other into the throttle body.

Check fuel pressure, also is it holding when the engine is shut off.
My guess would be fuel pump.

Did you try just to pull down the injectors into the manifold, so the 3rd o-ring sits firmly on the edge?
If the injectors are too high in the rail, fuel can pass bellow the upper o-ring. The bores in the rail are cut way too deep and the edges are razor sharp.

No codes? I am surprised no one asked yet. An L98 hardly ever stalls without setting a code.

What a bunch of comedians. I'd buy a new car

http://www.corvettestoreonline.com/st ... ctid=3745&cat=322&page=31

When I took my spare apart for cleaning I shot a few pictures.
A good friend unfortunately had an engine fire, so I passed it along.
The grommet slides right into the base and is part of the wiring.

Hey Matthew,
thanks and happy birthday.
Axel

We just adjusted the valves on a new stroker going into the 91 of Vette91.
He got CompCams roller rockers with securing/locking bolts.

Do you guys use Loctite on these bolts?

Hey Matthew,
congrats on your new Audi. I can't remember to have ever seen one of those on German roads. Is that an Audi made in USA for the US only? German license plates sure wouldn't fit into the rear slot.
Have fun with the big brother von der Fahrvergnügen Gang.
Axel

Thanks again! Now I got it.
I'll report back when we tried it in his 88 with AT.

Hey TB, thank you for your input.
I know where to find bit $0036 and how to change it, but I lost you on this one: "E129: 15 36 01 BCLR L0036,#$01"
Where do I find that line in the prom, what address is that?
Thanks,
Axel

Hey TB, I was hoping you would chime in.
I probably won't get a 87/88 in my hands until the season starts.
I've got feedback from a 87 owner, he choose to ignore the light without telling me. I guess all 87/88 are affected after all, when switching to ARAP.
Thanks a lot for helping out here!
Axel

Thanks CC!
Taking the ECM line out is a good idea. My idea would be a wrong A4 OD relay, sending out a not needed signal to the cluster. That would at least explain, why some are affected and others not.

I'll have to read the hack and see, if I can just turn a switch in the eprom to eliminate this altogether.

At least now, thanks to the Gurus, I know what I am dealing with. I had no clue, when the owner was talking about a "D" showing up permanently.

Thanks again guys!!!

Searching the WWW I found some info, the "OD" is a 4+3 only thing. The "OD" is like a control lamp, showing whether OD has been manually engaged or not.
Some guys on the dark site have encountered the same problem with burning eproms. Of course that damn place never offers a solution, what a waste of time.

Thanks Matthew, that's some great info.

Now I just need to know, what turns the light on???

Another thing that puzzles me, why this 88 and not the other 87s and 88s I chiped.

If you don't see it in your 89, it could be an indicator light for the 4+3 manual transmissions only. 89 started with the 6 speed manual transmission, no more OD light needed.

Any 4+3 drivers around here? Would be good to know for sure.

Hi Gurus,
for an 88 automatic I wrote an 89 automatic Eprom. Never had a problem with 86, 87 and 89 Vettes. In this 88 the "OD" light comes on, which has never been seen before.
What causes the "OD" to come on in the first place? I this a sign for trouble or some sort of service light?
With the original 88 Eprom the light stays off, with the 89 Eprom it comes on right away, even without starting the engine.

I don't really know what to look for in the Eprom hack, without even understanding what causes the light to come on.

Here's a pic:

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Measure the resistance of the fuel injectors. If the measurements come out OK I would measure fuel pressure next.

click here for auto

or here for 6 speed

Those bins are all out there and not that hard to find.

http://www.corvetteactioncenter.com/g ... y/showgallery.php?cat=537

There you got the 75 specs. A split rear bumper was a one year only deal in 74!

Sorry for tapping into the dark site, but can't beat a pictured thread:Klick

The clamp holds some sort of foamed rubber which is acting as a filter. No connections on that side of the solenoid!