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Bringing a 1988 back to life

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Old 01-01-2018, 10:46 AM
  #21  
aklim
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Originally Posted by VikingTrad3r View Post
do this to isolate the leakdown source.

get a friend. grab two sets of pliers and wrap tape around teeth on pliers. black tape works best.

remove the fuel hatch and the rubber splash tray.

one of you stand at back with pliers in hand ready to sqeeze the fuel sending and return line.

one guy in fromt seat turns key on (nor car on)


wait for pump to do its cycle. then the guyat back clamps both send and return line. i use vice grips. not too tight. dont want to damage lines.

now watch the pressure. does it bleed off???

if yes, gently pull the vac line off the fpr and see if there is fuel wet or smell. if yes, u have a leaking fpr. if not, if its dry or no smell, your injectors are leaking or your fuel is leaking from elsewhere. if you dont see fuel pooling anywhere then your injector(s) are leaking.

do not replace with multecs. call jon at fuel injector connection and order whatever he recommends.

lets us know how that test turns out and well guide u from there.
Couldn't you simply it? Use hose crimpers and turn the car to run mode. That should get fuel up there and pressurized. It's only 2 seconds so, no biggie.

http://www.sears.com/craftsman-hose-...FfPJ4wcdOjcHHg
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Old 01-02-2018, 05:17 PM
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Did some further exploratory work this afternoon. Checked vacuum lines, seemed OK and in place. Found that distributor turned real easy. Looks like the PO had his hands on it to try and set the timing. Cranked it over a few times and adjusted it small amount each time (counter-clockwise). It appeared to be oriented clockwise a lot. Each turn smoothed things out and the backfiring quit. Runs better, but at a very high idle. Didnít let it go for more than a few seconds. Fuel pressure was in 40ís. FPR or vacuum issues ?? Any ideas ? I know the distributor need tightened up.

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Old 01-02-2018, 07:36 PM
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You need to set the timing with a timing light not SOTP.
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Old 01-03-2018, 05:09 PM
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Originally Posted by aklim View Post
You need to set the timing with a timing light not SOTP.
It gets rough tuned by ear until it will stay running, then set with my light. Right now it would take 3 people....1 to keep it running, 1 to turn the dist and 1 to watch the light.
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Old 01-03-2018, 05:17 PM
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Originally Posted by skyhawk50 View Post
It gets rough tuned by ear until it will stay running, then set with my light. Right now it would take 3 people....1 to keep it running, 1 to turn the dist and 1 to watch the light.
Are you saying there's so much adjustments needed? You may have to time it after you set it up with TDC on 1
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Old 01-04-2018, 10:05 AM
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Originally Posted by aklim View Post
Are you saying there's so much adjustments needed? You may have to time it after you set it up with TDC on 1

It was waaay off. Getting better. Still dealing with the rapid drop of fuel pressure with key on. My wife turns the key on, Iím positioned at the fuel tank with 2 vise grips, no matter how fast I clamp, FP still goes to zero in 1-2 seconds.
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Old 01-04-2018, 11:55 AM
  #27  
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Originally Posted by skyhawk50 View Post
It was waaay off. Getting better. Still dealing with the rapid drop of fuel pressure with key on. My wife turns the key on, Iím positioned at the fuel tank with 2 vise grips, no matter how fast I clamp, FP still goes to zero in 1-2 seconds.
Put aside the timing for a bit. Work on something else.

Are you saying that you let it pressurize the system and clamped the return and feed line? Are you sure one of them wasn't the evap canister? If so I would suspect either the tank pulsator or the fuel pressure regulator or the injectors. Remove the regulator hose after the pressure leaks down and see. If the FPR hose smells of gas. If not, either the injectors are leaking or the pulsator in the tank is bad.
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Old 01-04-2018, 01:07 PM
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ruling out both the send and return removes the pulsator from the potential failure points doesnt it?

if he clamped correct lines its either fpr inj or leaking onto the ground as u have said and has been said.
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Old 01-04-2018, 01:16 PM
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Originally Posted by VikingTrad3r View Post
ruling out both the send and return removes the pulsator from the potential failure points doesnt it?

if he clamped correct lines its either fpr inj or leaking onto the ground as u have said and has been said.
Good catch. Spaced that one out. I'm suspecting regulator but if not, injectors and then might as well do regulator while you are there.
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Old 01-04-2018, 02:09 PM
  #30  
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I have an 1988 Coupe that sat for a few years and when I tried to bring it back to life the fuel pressure would go up but slowly and then a bad injector helped it go back down quickly.

There were several issues that my car had before I resolved the fuel one. I found that my oil pressure switch was not connected and since the computer did not see oil pressure it would not activate the fuel pump. The problem here was a PO had tried to solve a problem by changing terminal connections but he was a poor crimper. The wire at the switch was loose and that kept the fuel pump from energizing. When I jumper-ed the relay the pump came right on. Then I found corrosion on my fuse block which led to no/low voltages at various points in the car. After all these were done I was ready to tackle the fuel issues.

In the end of this I discovered that my fuel supply line had rusted almost completely shut. It would allow some pressure to build but not enough for the car to run. If you turned the key to "run" it would build to 42 psi but with no flow rate to speak of the car could not run.

I took a 20' length of Ethanol-rated high-pressure fuel line and went from the pump output on top of the gas tank to the input of the fuel filter and from there the car ran perfectly again.

I ordered both lines from Classic Tubing but after getting them decided that the rubber jumper made more sense. Otherwise I would have to dismantle the entire rear of the car to run the lines in their original positions. As of now it has a Stainless AN line going to the fuel filter from the tank output.

Once I got the car running and looking fair I wanted to drive it. The moment I pushed on the brake pedal it went to the floor. Turns out that I have rusted brake lines going into the box with the ABS equipment. In my ABS box I found another line that is swollen and obviously damaged. Here came Classic tubing again, I need an account with those folks...

Reviving a car that was not put away properly can be a giant hassle and may not be worth all the work unless you can do it yourself. I have a great running L98 but no operating brakes as currently I am replacing the lines to all the brakes. I am not just patching the lines, I am replacing them. I want this car to be as safe as it can be.

Not having a lift I might have to have the lines replaced by my favorite Afgan mechanic whom I trust to do it right. I have already put on new calipers and rotors and am looking forward to having pressure in my brake lines soon.

My best advice is to go over the car multiple times and look for anything. If you see a swollen line or a anything be sure to investigate thoroughly!

I hope that the New Year is good for all of you!
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Old 01-04-2018, 02:27 PM
  #31  
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Originally Posted by ctmccloskey View Post
I found that my oil pressure switch was not connected and since the computer did not see oil pressure it would not activate the fuel pump.
You sure about that? Disconnected it reads 0 psi and according to you, that should disconnect the pump from power. IIRC, it started and ran so I think it was just a secondary circuit
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Old 01-04-2018, 07:12 PM
  #32  
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Originally Posted by skyhawk50 View Post
It gets rough tuned by ear until it will stay running, then set with my light. Right now it would take 3 people....1 to keep it running, 1 to turn the dist and 1 to watch the light.
OK - Get one other person, hook up the fuel pressure gauge, and have them read it while you start the car and keep it running. Clearly - the way the pressure is dropping after the pump turns off you have a fuel supply issue - (most likely regulator - but it could also be the check valve in the pump, a badly leaking injector or two or a partial blockage in one of the supply lines, but IF you are maintaining around 43 psi while the engine is running - then you go one direction - if not - you go another direction.

If you do not maintain 43 psi when running - you need to figure out if it's the pump or a problem with a restriction in a fuel line. (The easiest thing to do is to try to blow compressed air through the lines and see if the air appears to flow freely - if it does - replace the pump - if not - see if you can find the restriction.

If you do maintain 43 or so psi while running - you should probably check for leaking injectors - pull all the injectors (but keep them hooded to the fuel supply line), then jumper the fuel pump relay to run the pump and see if any of the injectors are leaking. If you have badly leaking injectors - you have probably found at least some of the problem. If not - you need to keep looking - but at least you know that you have enough fuel pressure, and that the injectors aren't just pouring gas into the engine.

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Old 01-09-2018, 09:10 PM
  #33  
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Well, outside temps finally went above freezing. Got something avcomplished today. I replaced the fuel pump. Seems to have fixed the fuel pressure. Starts, runs, then idles up to very high idle. I got a new fuel pressure repair kit, pkenum gasket set and new injectors to install ( yes, theyíre from FIC ). Trying to cover all my bases while the plenums off. I canít help but thing I got a combination of issues. Hopefully tomorrow I get the plenum off and my new parts on.
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Old 01-12-2018, 07:51 PM
  #34  
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Plenum back in place, new injectors installed. Starts, runs rough, can keep running by feathering the gas. Iím about out ideas.
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Old 01-13-2018, 09:10 AM
  #35  
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Look - You're making progress - so don't give up in frustration. (It is perfectly "OK" to walk away for a little while - but you gotta go back).

So - it sounds like you've got fuel pressure and the injectors are now good - so the fuel supply is now supposedly "fine".

OK - so the most likely problem is now most likely down to a vacuum leak, the Ignition system or the EFI system not sending the injectors the right pulse width.

So - I'd recommend the following - hook up a vacuum gauge and see what kind of vacuum you have at steady state say 2,000 - 2,500 RPM, and then slowly bring down the engine speed (while watching the vacuum gauge) to see what the vacuum looks like at lower engine speeds. You could have a vacuum leak, and the EFI computer does not understand how to compensate for that. Normally a car engine will produce on the order of 18 - 20 inches of vacuum at idle. If you see the vacuum getting somewhat lower than that as you approach idle - you have likely identified a problem.

Next - pull the plugs and give them a good looking over. Are they all uniform - or is one (or more) "different" ??? If a plug is fouled - you should investigate why. Bad wire - bad cap/rotor ??? Oil fouling ???

One shortcut I have been able to successfully use involves taking an IR temp "gun", and with the engine running at a fixed speed - check the temp on each exhaust "port" (needless to say - this works better with headers than with stock manifolds) - but do all the ports seem to be around the same temp -or are there a couple that "lag"- that typically means those cylinders are misfiring. (Alternatively - have someone hold the engine at some given RPM it will run at - disconnect one plug wire and see how the engine responds... Then reconnect that wire and pull the next one. Each cylinder you "disconnect" should cause an roughly equal response - if one doesn't that cylinder is not doing an equal amount of work - if you can't find a problem with Ignition to that cylinder - then you have something else going on. (Warning - the Modern Ignition systems produce a pretty health amount of spark energy - use insulated pliers to pull the wires, and try not to be touching any metallic part of the car when doing this (ask me how I know this)...

Just keep working at it - you WILL get there !!!
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Old 01-13-2018, 09:35 AM
  #36  
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Originally Posted by skyhawk50 View Post
Plenum back in place, new injectors installed. Starts, runs rough, can keep running by feathering the gas. Iím about out ideas.
Dumb question but is the timing set right? When the engine is warmed up after feathering, what is the IAC count? Can you disconnect the MAF sensor and see what happens? You said you got 37 psi. How did you get it? Did it spike up there and hold? I thought it was 43 psi but might be wrong.
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Old 01-14-2018, 12:23 AM
  #37  
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a vac leak would cause a very high idle.

if its REAL bad like a huge hose off the brake booster the cigar smoke test will see it. put tape over the throttle body. pull the rubber off the brake booster and blow cigar smoke in. if u see smoke curling outsomewhere thats one of your problems but im doubting it. the cigar test is a fast and fun method to rule out vac leaks.

as Aklim is eliding to, if you have a scanner (cant remember upthread if u said u do) or an aldl cable with tunerpro then you can check in on all your sensors. The IAC is one that controls your idle in cooperation with the mechanical position of the trottlebody.

for starters id think u can follow the minimum idle adjustment. google this for our cars. Ak will quickly point out correctly that its not as good as real time adjusting the mechanical losition while monitoring the iac position BUT until u acquire a scanning method id start with minum idle adjustment.

If it wont hold idle with min idle adjustment, let us know and we can help u onto the. ext step.

you WILL solve it. its a puzzle waiting to be solved.

so u have a few things mentioned for next steps

1. check the vac leak via smoke test.

2. do minimum idle adjustments

3. if that doesnt work then order up the scanning aldl cable and get tuner pro rt onto a laptop and get the data file for your 88 bette.

Come back here and let us know how it goes. u will get it.
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Old 01-14-2018, 01:07 AM
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Originally Posted by VikingTrad3r View Post
if its REAL bad like a huge hose off the brake booster the cigar smoke test will see it. put tape over the throttle body. pull the rubber off the brake booster and blow cigar smoke in. if u see smoke curling outsomewhere thats one of your problems but im doubting it. the cigar test is a fast and fun method to rule out vac leaks.

for starters id think u can follow the minimum idle adjustment. google this for our cars. Ak will quickly point out correctly that its not as good as real time adjusting the mechanical losition while monitoring the iac position BUT until u acquire a scanning method id start with minum idle adjustment.

3. if that doesnt work then order up the scanning aldl cable and get tuner pro rt onto a laptop and get the data file for your 88 bette.
He only has a certain number of hoses. Unplug each one and cap off the nipple. IF it holds an idle, plug the hose back in. If it doesn't, there is your problem. If it does, move to the next nipple cap.

Today, tomorrow or the day or week or month after, he is going to need it. What then? Are you sure it is going to be in stock? My Auto Xray company was bought out by Actron and it doesn't support it any more. Buy today before they phase it out. Not like he needs it today since it is winter nor will he never again need it. And no, it is not as good since it relies on everything else being perfect. And also, you won't be able to see what the ECM is reading like the temp sensor or O2 sensor or whatever you want.

Supposedly the ALDL Driod works and definitely the MT2500 from SnapOn works. Definitely the GM Tech1 will work and be able to read all kinds of data from the BCM.
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Old 01-14-2018, 02:28 AM
  #39  
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if aldl droid is solid its worth trying! my kids got android tablets for xmas ill give it a try.

tunerpro rt works but its a pita to configure. its free though so no complaints
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