changed water pump, having fuel issues
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
Likes: 287
From: Minnesota
changed water pump, having fuel issues
hey guys, i'm hoping for some advice before i start trouble shooting (not the greatest engine mechanic)
i just changed the water pump on my 1987 (i also did a couple other things while i had it apart)
1) Changed water pump
2) Added smog delete pulley (did this before i pulled the water pump, it started and ran fine when i tested it)
3) Cleaned the battery area (removed the tray and painted it, took the grounding block out and wire brushed all the cables going to it)
Everything is back together and it's not getting gas (i think).
I finally got it to run but it required giving it some gas...i also had to keep on the gas or it wanted to die (it died as soon as i let off the gas).
Any areas i should focus on? i have not checked the fuel pressure but the valve does leak gas when depressed.
I did NOT replace the o-rings on the 2 large lines that need to be removed when replacing the water pump...maybe this is the problem?
would some type of a vacuum leak affect gas to the cylinders?
It ran just fine before this project so i'm not looking at things like fuel pump or injectors (which are only 2 years old).
for what it's worth, i did change the opti on my Lt1 car and had no issues with that so i guess i am somewhat capable haha
i just changed the water pump on my 1987 (i also did a couple other things while i had it apart)
1) Changed water pump
2) Added smog delete pulley (did this before i pulled the water pump, it started and ran fine when i tested it)
3) Cleaned the battery area (removed the tray and painted it, took the grounding block out and wire brushed all the cables going to it)
Everything is back together and it's not getting gas (i think).
I finally got it to run but it required giving it some gas...i also had to keep on the gas or it wanted to die (it died as soon as i let off the gas).
Any areas i should focus on? i have not checked the fuel pressure but the valve does leak gas when depressed.
I did NOT replace the o-rings on the 2 large lines that need to be removed when replacing the water pump...maybe this is the problem?
would some type of a vacuum leak affect gas to the cylinders?
It ran just fine before this project so i'm not looking at things like fuel pump or injectors (which are only 2 years old).
for what it's worth, i did change the opti on my Lt1 car and had no issues with that so i guess i am somewhat capable haha
Instructor
Joined: Mar 2019
Posts: 142
Likes: 36
From: Southern New Hampshire
Perhaps you are not starving for fuel. You said you have to give it gas to keep it running "i also had to keep on the gas or it wanted to die (it died as soon as i let off the gas)."
It is possible you have a vacuum leak. A vacuum leak will cause a low idle and giving it more gas will keep a car running. Look around for any vacuum lines you may have disconnected and did not reconnect. I am sure other will be along with better advice.
It is possible you have a vacuum leak. A vacuum leak will cause a low idle and giving it more gas will keep a car running. Look around for any vacuum lines you may have disconnected and did not reconnect. I am sure other will be along with better advice.
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
Likes: 287
From: Minnesota
Perhaps you are not starving for fuel. You said you have to give it gas to keep it running "i also had to keep on the gas or it wanted to die (it died as soon as i let off the gas)."
It is possible you have a vacuum leak. A vacuum leak will cause a low idle and giving it more gas will keep a car running. Look around for any vacuum lines you may have disconnected and did not reconnect. I am sure other will be along with better advice.
It is possible you have a vacuum leak. A vacuum leak will cause a low idle and giving it more gas will keep a car running. Look around for any vacuum lines you may have disconnected and did not reconnect. I am sure other will be along with better advice.
Still the same symptoms. Wont start on it's own.
When i turn the key, it initially for a split second acts like it's firing but immediately just starts cranking. if i give it gas it fires up and runs just fine (as long as i maintain pressure on the gas pedal). i slowly let off and i can get it to idle as low as 400rpm (rough idle) and she dies as soon as it stops getting gas.
I let her purr at 1500 rpm's long enough to get to 150 degrees and i have no engine codes at all.
I'm done for the day, it's getting late and i live in a townhome so time for a beer and distractions.
I'll be checking here though if anybody has suggestions. I can probably get a fuel pressure gauge tomorrow but not sure if that affects it starting or not since it runs just fine once i get her going.
Last edited by mark970; May 16, 2020 at 08:54 PM.
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
Likes: 287
From: Minnesota
Good news, if there is any is that i have no problems with my water pump replacement 
(no leaks is what I mean...clearly I'm having problems)
(no leaks is what I mean...clearly I'm having problems)
Last edited by mark970; May 16, 2020 at 08:39 PM.
Racer
Joined: May 2020
Posts: 345
Likes: 68
From: New Jersey
It’s rare but 1 in 10 I’d say has to “relearn” how to run once the battery is disconnected on the OBDI systems, when you remove power from the ECM, it will erase the Ramdom Access Memory (RAM) part of the computer.
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
Likes: 287
From: Minnesota
interesting, i've never heard of this but anything is possible. Are you saying the RAM has been removed which could be causing the problem or that i need to perform an act to erase the RAM so the ECM can start over?
Racer
Joined: May 2020
Posts: 345
Likes: 68
From: New Jersey
Random Access Memory is short term memory. The tps and other sensors like that have been erased. It’s not common but it does happen. Take it for a ride and see how it is. Sometimes it can fake up to 150 miles. You might try disconnecting the battery again. Cycle the key once to dump anything stored and then rehook the battery and see how it idles before you have to drive 150 miles.
if there were a check engine light on it erases the RAM until it detects the problem again. That is why the light goes off.
make a little more sense now?
if there were a check engine light on it erases the RAM until it detects the problem again. That is why the light goes off.
make a little more sense now?
Last edited by WarlockIII; May 16, 2020 at 09:25 PM.
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
Likes: 287
From: Minnesota
Random Access Memory is short term memory. The tps and other sensors like that have been erased. It’s not common but it does happen. Take it for a ride and see how it is. Sometimes it can fake up to 150 miles. You might try disconnecting the battery again. Cycle the key once to dump anything stored and then rehook the battery and see how it idles before you have to drive 150 miles
btw...i didn't know there was even such a thing as RAM in 1987 hahahaha
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Team Owner
Joined: Jul 2004
Posts: 28,475
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From: Hartford WI
Random Access Memory is short term memory. The tps and other sensors like that have been erased. It’s not common but it does happen. Take it for a ride and see how it is. Sometimes it can fake up to 150 miles. You might try disconnecting the battery again. Cycle the key once to dump anything stored and then rehook the battery and see how it idles before you have to drive 150 miles.
if there were a check engine light on it erases the RAM until it detects the problem again. That is why the light goes off.
make a little more sense now?
if there were a check engine light on it erases the RAM until it detects the problem again. That is why the light goes off.
make a little more sense now?
Are you sure that the check engine light erases the RAM? Why would it do something like that?
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
Likes: 287
From: Minnesota
it's a new day so a fresh start! I'm going to focus on a couple areas...i spent 3 days on this project, partly because since i took the front of the engine apart, i took the extra steps to clean almost everything that i could remove (clean with soapy water, nylon brush, shop rags ect... and in some cases, remove brackets and spray some paint on them). So I'm going to go around and clean all the electrical connections with appropriate cleaner. i know my IAC harness connection is broken (came to me this way) so i will make sure thats a) in all the way and b) orientated properly if it's a fitting that will go in at 90 degrees (which would be rare, but it is a square harness).
If that does'nt work, I'm going to investigate the grounding block (bolted to the frame,down behind the battery tray) that i took apart to clean.
The car ran fine before i got my hands on it so it has to be related to something that i did...action vs. reaction thing i'm thinking!
If that does'nt work, I'm going to investigate the grounding block (bolted to the frame,down behind the battery tray) that i took apart to clean.
The car ran fine before i got my hands on it so it has to be related to something that i did...action vs. reaction thing i'm thinking!
Last edited by mark970; May 17, 2020 at 08:01 AM.
Racer
Joined: May 2020
Posts: 345
Likes: 68
From: New Jersey
I located this thread from 2003 maybe it explains in better: https://www.corvetteforum.com/forums...isconnect.html
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
Likes: 287
From: Minnesota
I located this thread from 2003 maybe it explains in better: https://www.corvetteforum.com/forums...isconnect.html
Racer
Joined: May 2020
Posts: 345
Likes: 68
From: New Jersey
Here’s one from 2014 that may explain it better still: post #3 https://www.corvetteforum.com/forums...r-relearn.html
Last edited by WarlockIII; May 17, 2020 at 09:05 AM.
Racer
Joined: May 2020
Posts: 345
Likes: 68
From: New Jersey
I’m not trying to say I’m right or wrong. There is no right or wrong, only applied knowledge. I was merely trying to help and offer what advice I could. I apologize for not being able to explain it better.
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
Likes: 287
From: Minnesota
Here’s one from 2014 that may explain it better still: post #3 https://www.corvetteforum.com/forums...r-relearn.html
I did some digging myself and since i cleaned my components with a brush and soapy water, i could have easily gunked up the electrical pin connectors, I'm going to clean those first and check my broken IAC harness and make sure that's ok (my issue is idle anyways...good place to start, not to mention i disconnected this a half a dozen times over the past 3 days).
I did read those threads you linked and i did find them valuable so again, thanks for helping and contributing!!!
Last edited by mark970; May 17, 2020 at 09:20 AM.
Racer
Joined: May 2020
Posts: 345
Likes: 68
From: New Jersey
Thanks. But I ask one favor. When you resolve the issue would you be kind enough to post it for future reference. Title it clearly and post the resolution. Your experience may help someone in the future.
Drew
Drew
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
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From: Minnesota
I'm going to wait a bit before going into the garage. it's early on a Sunday and I'm not going to be cranking the engine this early in my town home community soooo I'm practicing patience because i want to start the car after every change i make so i know what exactly fixed my problem instead of performing 3 tasks and not knowing which fixed it. This car has Dynomax Super Turbo mufflers and i really don't care for it so until i swap the exhaust out to an LT1 system (yes i know i have an L98 car) I'm going to have to be patient.
Last edited by mark970; May 17, 2020 at 09:38 AM.
Team Owner
Joined: Jul 2004
Posts: 28,475
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From: Hartford WI
Here’s one from 2014 that may explain it better still: post #3 https://www.corvetteforum.com/forums...r-relearn.html
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
Likes: 287
From: Minnesota
Post 3 and 7 mentions that it defaults to whatever it was programmed to from the factory, aka baseline. Regardless, when you go WOT, it goes back to baseline too. I guess what I am thinking is that even if we went with baseline or open loop before the car meets the condition to get into closed loop, it should not run like what he is having.
Thread Starter
Drifting
Joined: Apr 2017
Posts: 1,336
Likes: 287
From: Minnesota
FIXED!!!
I'll elaborate more later, i need to get out and run errands (this project took my entire weekend).
I have a broken IAC connector on the harness side (i see an upcoming project!)
Water Pump replacement was a success, no leaks however it's getting hot, crazy hot so i need to read again how to burp an L98 (LT1 was pretty simple).
For the pump, I went with Flow Kooler #1688. I had to install a new heater hose tube, couldn't get my old one out and guess what, there aren't any out there (long and low profile) so i had to use what's available...there were a couple snags but it's done now.
I'll elaborate more later, i need to get out and run errands (this project took my entire weekend).
I have a broken IAC connector on the harness side (i see an upcoming project!)
Water Pump replacement was a success, no leaks however it's getting hot, crazy hot so i need to read again how to burp an L98 (LT1 was pretty simple).
For the pump, I went with Flow Kooler #1688. I had to install a new heater hose tube, couldn't get my old one out and guess what, there aren't any out there (long and low profile) so i had to use what's available...there were a couple snags but it's done now.