87 LXI starting issues

[Catalyst]

Hey everybody!

It's been a while since I've visited these forums, mostly because I have been storing my accord in my garage, and driving my DD (95 ranger). Anyways, my GF took my truck for the week, and so I have to drive the honda. It usually runs like a dream for me, and always has... but every now and then, it would do this weird thing where I would go to start it, and it would crank, turn over and run for a split second, then just go back to cranking, and I would have to fight with it for a while to get it to start.

It has gotten worse and worse this week, and it is now doing it everytime I go to start it. It eventually will start, but run really rough (like its running on 2 cyl), and after feathering the gas a bit, it runs fine.

Now, the car has always intermittenly had the CEL come on while driving, (Code 12 EGR), but it passed smog like this, and it has never affected the way it runs. Although the idle can be a bit wierd when its on. If the CEL comes on, it will start no problem (fail safe tuning?)

So I'm stumped, after looking around the engine bay for a while, I noticed two vacuum lines unconnected. It has been this way since I have owned the car, or since I installed my short ram intake a few years ago. I have no clue if this is part of the problem, or not, seeing as how it has always run fine like this.. Here are the vacuum lines in question:

http://i10.photobucket.com/albums/a104/Supra1evan/my%20car/vacuum1.jpg

and

http://i10.photobucket.com/albums/a104/Supra1evan/my%20car/vacuum2.jpg

All fluid levels are fine, and like I said, when it starts it runs great, just getting it to start is the hard part. Any suggestions on where I should start? Should I route those two vacuum lines where the are supposed to go? I'm sorry for sounding like a noob, but it when it comes to vacuum, I have very little knowledge of how it all works. Any help is much appreciated. Thanks!

[87roach]

Not sure about the vacuum lines. If you've just been storing it I would think stale gas right off the bat, maybe a gummed up fuel filter.

[Catalyst]

I was thinking the same thing too, but I have been driving it for the past few weeks on and off and its ran beautifully, fresh gas and all.

Now here is something strange, went out to see if it would start today, and it fired up first try (ran crappy for a few seconds, then was fine) And its starting up every time I try.

So strange...I don't get it! I know its going to do it me again later...

[Catalyst]

Update #2..

Decided to seafoam the car for the first time..... and holy cow did it smoke!

Anyways, after that, I drove it to town and back a few times shutting it off randomly, and its starting / running like a champion again... so I hope that solved my problem...(*crosses fingers*)

I LOVE Seafoam. Anyways, some insight on those loose vacuum lines would still be nice, also, I still seem to get the code 12 (EGR) after about 10 mins of driving. I know one of the lines is for the AC Idle boost.. but even with that hose unplugged it idles down just fine with the AC on. The other sensor... I am still not sure what that is or how it should be hooked up? Idle Control Solenoid maybe?

[Catalyst]

Update #3

Well I didn't fix it. I thought it was ok because it started and ran great all day long, but that's because I had been parking it in the garage. When It sat out in the sun, and got hot, it wouldn't start... so all signs pointed to the Main Relay.

Took it out, re-soldered the joints, and It seems to have fixed it..

However something weird happened after I popped the relay back in and fired it up.. I got a code 6 (Coolant temp sensor) randomly once, then I reset the ECU and it went away, and I haven't seen it since. I still get Code 12 after a while of driving.

I pulled a vacuum on the EGR while it was running, and it started stuttering, but didn't die no matter how much vacuum I pulled.. I think it was like 20in or something like that.. So does that mean its time for a new valve? Or is the engine not supposed to die, but sputter?

[Catalyst]

Update #4

Turned out to be the Coolant temp sensor, or TW sensor.

I went to pick n' pull, grabbed a new main relay, FPR, both temp sensors, MAP, EGR valve, EGR solenoid, and started replacing them one by one... started with the main relay, nope..... then the FPR.... nope..... then the infamous TW sensor.. BINGO! Fired right up and ran like a champion... test drive it several times and its running great.... now to figure out the EGR (12) CEL.

Just updating this thread to help others for future reference.

[Dr_Snooz]

I don't really know the '87 FI setup but your one vacuum line is connected to what looks like the fuel pressure regulator on my '89.

Putting vacuum on the EGR valve should stall the engine. Cleaning it would be a good start. Just pull it off and remove any carbon crud on the valve or in the intake. If it gets more complicated than that you'll want to get ahold of a factory service manual. The troubleshooting diagnostics for the smog controls are second to none. You should have it figured out quickly using that.

For the vac lines, just hook them back up. You'll know pretty quickly if they are wrong.

[Catalyst]

thanks Doc, I'm going to have to dive into the manual.

I played around with it a bit today. I first replaced the EGR valve with a junkyard unit (cleaned and whatnot). The idle improved, but the code still came on at about 65. So back to the garage, reset the CEL and moved on.

Opened up the black box, to clean the solenoid and small CVC filter... and I can't get 2 of the damn metal bracket screws off inside the black box... so that was a negative. I blew some compressed air up the vacuum lines to maybe help unlodge some crud built up. I noticed while I was doing this, lines #17, and #18 were unhooked, and just hanging.... most likely from when I installed my short ram. I hooked these up to a T, and ran the line into my intake, and tried again.... still code 12, and when the CEL comes on, the idle goes up and down... sound like i really need to get those 2 welded on screws off inside the black box so I can clean everything in there. :/ I'll keep trying. I also connected those 2 drivers side Vac lines (one for the AC idle boost, and some Idle Control Solenoid or something like that.... I connected them both to ports on the intake... resettin the CEL and I'll try again.

[rc00netzero]

One of those hoses (bottom pic) goes to the idle control solenoid. Someone probably disconnected it because they found it stopped the loping idle you are now getting. This is triggered by the CEL. The ECU disables normal idle control and opens the idle control valve to increase idle. IF your base idle (no CEL) is high that will push idle above 1500 - where the ECU closes the solenoid. Idle drops and the ECU re-opens the solenoid, etc, etc, etc. Adjust your base idle lower if it's too high. Mine does the code 12 too it's a common issue but has many causes. Good Luck :)