New engine problems
Thread Starter
Melting Slicks
Joined: Oct 2000
Posts: 2,019
Likes: 2
From: Na
New engine problems
I may be crazy and imagining things but it seems that when I rev my engine manually the RPMs kind of hang for a while before falling back to idle. Any ideas what may be causing this? Nothing is sticking as far as the TB or accel. cable. I also have a cold idle problem as where the RPMs will fluctuate between 700-1200rpms until it goes into closed loop. BTW, this is a new engine w/ all new parts. I just recently finished it and these problems began from the get go, specs are in my sig. TIA.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Example: With my 86E in open loop, I had a idle surge that caused the RPM to go up and down. Once the ECM went closed loop the idle surge went away. The idle was steady. This made it sort of difficult to locate the leak in a matter of 3-4 minutes, until closed loop. Found the vac leak the size of a pencil eraser on the end of the PVC aluminum vac tube. Plug the end and no more surging.......
Thread Starter
Melting Slicks
Joined: Oct 2000
Posts: 2,019
Likes: 2
From: Na
Thanks guys, A vacuum leak was what I though at first. But after looking for a leak I couldn't find one. I even tried the propane trick w/o luck. I'll give it another try.
Also forgot to mention the engine is very hard to start when cold as well. I deleted the cold start injector. Maybe that has something to do w/ it?
Also forgot to mention the engine is very hard to start when cold as well. I deleted the cold start injector. Maybe that has something to do w/ it?
Last edited by NUckINg FuTS; Dec 30, 2006 at 11:16 AM.
Racer
Joined: Dec 2005
Posts: 384
Likes: 0
From: Chicago IL
Thanks guys, A vacuum leak was what I though at first. But after looking for a leak I couldn't find one. I even tried the propane trick w/o luck. I'll give it another try.
Also forgot to mention the engine is very hard to start when cold as well. I deleted the cold start injector. Maybe that has something to do w/ it?
Also forgot to mention the engine is very hard to start when cold as well. I deleted the cold start injector. Maybe that has something to do w/ it?
I'de imagine a vacume leak, but could be a number of things. My 357 with a miniram starts right up and holds idle w/o a problem. Who did the chip? Could be a number of things. Can you hook up diacom or some type of scanner to it?
BTW, what part of chicago do you live in?
Thread Starter
Melting Slicks
Joined: Oct 2000
Posts: 2,019
Likes: 2
From: Na
your cold start injector has nothing to do with it at all. Ive been without a cold start injector since 2000 (that was 2 motors ago).
I'de imagine a vacume leak, but could be a number of things. My 357 with a miniram starts right up and holds idle w/o a problem. Who did the chip? Could be a number of things. Can you hook up diacom or some type of scanner to it?
I'de imagine a vacume leak, but could be a number of things. My 357 with a miniram starts right up and holds idle w/o a problem. Who did the chip? Could be a number of things. Can you hook up diacom or some type of scanner to it?
My chip was done by Jesse Azzato (ski_dwn_it). I am doubting its the tune. This is your basic 219/superram combo which I know Jesse has alot of experience with.
I am on the North side, Belmont and Cumberland but the Vette is in Indiana.
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Racer
Joined: Dec 2005
Posts: 384
Likes: 0
From: Chicago IL
its proabbly something "minor" i'de double check the tps seting. reset the iac and check for vacume leaks in the manifold and the vacume lines.
Im right off the lake front by the museum of science and industry. About 15 minutes form n/w indiana.
I'll be spending as much time as possible at US41 when it open up next year. Hopefully we can meet up and make some 1/4 mile runs. I think it would be fun and informative for everyone to do some s/r vs miniram runs!
Im right off the lake front by the museum of science and industry. About 15 minutes form n/w indiana.
I'll be spending as much time as possible at US41 when it open up next year. Hopefully we can meet up and make some 1/4 mile runs. I think it would be fun and informative for everyone to do some s/r vs miniram runs!
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
NUckINg FuTS, do you still have the CSV? Is it still functional in the ECM or have you had it tuned out?
The CSV is only active during cranking at temps below 95*. The switch times out at ~8 seconds after the engine is running. Any cranking temps above 95* and the CSV is not active. If anything in the system is faulty causing the CSV not to work, will cause extended cranking times... cold.
The CSV is only active during cranking at temps below 95*. The switch times out at ~8 seconds after the engine is running. Any cranking temps above 95* and the CSV is not active. If anything in the system is faulty causing the CSV not to work, will cause extended cranking times... cold.
Thread Starter
Melting Slicks
Joined: Oct 2000
Posts: 2,019
Likes: 2
From: Na
NUckINg FuTS, do you still have the CSV? Is it still functional in the ECM or have you had it tuned out?
The CSV is only active during cranking at temps below 95*. The switch times out at ~8 seconds after the engine is running. Any cranking temps above 95* and the CSV is not active. If anything in the system is faulty causing the CSV not to work, will cause extended cranking times... cold.
The CSV is only active during cranking at temps below 95*. The switch times out at ~8 seconds after the engine is running. Any cranking temps above 95* and the CSV is not active. If anything in the system is faulty causing the CSV not to work, will cause extended cranking times... cold.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Yes, cold start injector. Yes, it can be deleted out of your chip. It's there to help with cold starts as the fuel delivery is not enough with the 85-88 165 ECM's. In 89 the CSV was deleted when the ECM was upgraded (faster). There is more to this, but thats the run down.
Melting Slicks
Joined: Jul 2006
Posts: 3,356
Likes: 1
From: Chesapeake Va
AAAAHHHHHHH................the old smoke machine. Its like magic, aint it Rob? Its one of those things you cant believe you been livin without once you have one....
PS. If you have a scanner, what are the IAC counts? This will tell you if the IAC is trying to bring the idle down and is unable to due to a vacuum leak.
PS. If you have a scanner, what are the IAC counts? This will tell you if the IAC is trying to bring the idle down and is unable to due to a vacuum leak.
Last edited by edcmat-l1; Jan 2, 2007 at 08:01 AM.
Thread Starter
Melting Slicks
Joined: Oct 2000
Posts: 2,019
Likes: 2
From: Na
I heard about the "smoke machine". But I don't have the luxury of taking my car to a shop as it is in many pieces now. I'll have to figure this one out on my own and w/ the help of you guys. I'm reseaching on buying an ALDL cable and hooking it up to a laptop to get a scan. Any ideas on a good place to buy one?
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Craig Moates sell the Cables and USB-ALDL converter. About $80 plus shipping. He can help you with any questions and I highly recommend him.
You can try and blow cigar smoke into the TB with the engine running.
You can try and blow cigar smoke into the TB with the engine running.
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
The easiest way to locate a vacuum leak is to get some good starter fluid from an autoparts store. The stuff works PERFECT and will detect any leak in a few seconds. To start have a garden hose ready and nearby, the stuff if flamable, but if you just use it in little squirts, letting it evaporate you will be perfectly fine...the hose is just for precaution if you do get a flame...done it many times and never had an issue...found MANY leaks that went undetected with other methods.
To start you want your car running and at temp, do it where you can easily hear the motor RPM changing - not near heavy traffic etc if you live near a busy street. To get a feel for what the motor will do when it sees the starter fluid, spray a little down around the air cleaner - you should hear the motor rev up a little ~300rpms.
THen just proceed to spray it, again in small amounts, around all the seams of the intake. When you get to an area leaking it will rev the motor like it did with the spray near the air cleaner.....THAt is your vacuum leak area!
It is very easy and if you use caution very safe!
Good luck and if you need anything let me know!
Jesse
Ours had a bad time with returning to idle speed with the vac leak.
Melting Slicks
Joined: Jul 2006
Posts: 3,356
Likes: 1
From: Chesapeake Va
The easiest way to locate a vacuum leak is to get some good starter fluid from an autoparts store. The stuff works PERFECT and will detect any leak in a few seconds. To start have a garden hose ready and nearby, the stuff if flamable, but if you just use it in little squirts, letting it evaporate you will be perfectly fine...the hose is just for precaution if you do get a flame...done it many times and never had an issue...found MANY leaks that went undetected with other methods.
To start you want your car running and at temp, do it where you can easily hear the motor RPM changing - not near heavy traffic etc if you live near a busy street. To get a feel for what the motor will do when it sees the starter fluid, spray a little down around the air cleaner - you should hear the motor rev up a little ~300rpms.
THen just proceed to spray it, again in small amounts, around all the seams of the intake. When you get to an area leaking it will rev the motor like it did with the spray near the air cleaner.....THAt is your vacuum leak area!
It is very easy and if you use caution very safe!
Good luck and if you need anything let me know!
Jesse
Racer
Joined: Dec 2005
Posts: 384
Likes: 0
From: Chicago IL
I heard about the "smoke machine". But I don't have the luxury of taking my car to a shop as it is in many pieces now. I'll have to figure this one out on my own and w/ the help of you guys. I'm reseaching on buying an ALDL cable and hooking it up to a laptop to get a scan. Any ideas on a good place to buy one?
I have the diacom software, cables and laptop to hook up to your car. If intrested let me know. If your car is in n/w indiana its proabbly not too far from my home. I stay off the lake about 15 minutes from hammond indiana. let me know.