86 svo runs rough at idle

[red766]

ect

ok, will replace ect and see what happens.

I have to agree with Mike, the ECT can really foul things up for idle and part throttle cruise when the EEC is looking for it. Make sure all your harness connections around the intake are seated an also along the firewall behind the intercooler, where you could have bumped one with the ignition work. Here is a picture showing the little bugger that I found in my stash of pics. Don't go for one of the all plastic models, mine didn't last me 1 full season before giving out, I suggest a brass body one like in the picture. Good luck.

[ATTACH=CONFIG]42955[/ATTACH]

[svono50]

If you have a DVOM you can check the resistance across the 2 pins of the sensor to see if it has gone bad or not. I thought I had posted up the graph of the temp vs resistance, but can't seem to locate it. I will rescan and post up tonight when I get it so you can have a reference.

I did find my thread from back in 2009 on my failed plastic ECT sensor, so here it is: http://www.svoca.com/forum/showthread.php?23077

Kiwi, it is easy to keep clean when you take it apart enough times

[red766]

whatt is timing on my '86 with 5 spd supposed to be? there are no vacuum lines at the distributor to disconnect either.

what should it be at idle? what is idle rpm supposed to be to set timing? and what should timing be at 3500 rpm?

right now it is reading 30 degrees btdc at 1000 rpm.

[svono50]

You are correct on the no vacuum observation, the timing on our cars is controlled electronically. Your base timing with the 'spout' connector removed is 10 deg BTDC. With the spout connector in, as you measured, will float somewhere around 30 deg BTDC. The spout connector is simply a little black plug that is located in the TFI wire harness just off the side of the distributor. The wires to the spout connector are yellow. You can either pull the spout connector with engine off, start the car and take the timing or pull it while the engine is idling and take the timing. I have seen folks perform it either way, just note that you idle will change slightly when you remove the timing advance. Removing the spout connector disconnects the TFI/EEC from the timing circuit and their ability to advance/retard the timing, which allows you to read/set the 'base' timing. As long as your idle isn't 2000 rpm, your setting should be fine.

I scanned in the ECT page from the Slocum book and it is attached for your reference. A quick check with a DVOM across the pins of the ECT will give you a quick idea whether or not it is bad.

Manual - The Complete Turbo 2.3L EEC-IV Handbook_ECT_Pg 2-3.pdf

[svono50]

Here is the TFI page out the Slocum book for reference as well. Figured I should add this one along with the ECT, since you were asking about ignition timing. As for your question about the timing at 3500 rpm, I really don't have any idea what the timing advance would be at that rpm and no load. If someone on here has ever played with the various EEC tuners, then they may be able to tell you what the stock timing tables are and what you may expect for a value.

Manual - The Complete Turbo 2.3L EEC-IV Handbook_TFI_Pg 2-16.pdf.pdf

[red766]

next action items

bought new ect, .................can't install,...........need to get 1" socket,...so will install this wkend along with a good cleaning around the vam.... and I will replace plugs.... and put in new IAC

then will download codes again...........

i also plan on replacing vam rubber tubes/hoses and intercooler tubes, as soon as I figure out where to buy these.

question: did I read somewhere that there is a fuse behind the 'premium switch',....if so I can't find it....

[stockman1]

bought new ect, .................can't install,...........need to get 1" socket,...so will install this wkend along with a good cleaning around the vam.... and I will replace plugs.... and put in new IAC

then will download codes again...........

i also plan on replacing vam rubber tubes/hoses and intercooler tubes, as soon as I figure out where to buy these.

question: did I read somewhere that there is a fuse behind the 'premium switch',....if so I can't find it....

I know it's your money but a bit of diagnostic might save you from all the uneeded replacements. Try cleaning contacts on ECT and re run the test

[red766]

that is a nice clean engine by the way.... someday mine will be like that. anyway.

I took the upper intake manifold off to get the ECT out - which I did. Put a new brass
one in, along with new plugs and just a good general looking for loose /bumped
connections, spent a lot of time on the vam.... purrs like a kitten now..... however the scanner codes - no change,
21/25/41/77......... on my ect, ever since i've owned the car the engine temp gauge hasn't
gone about the 'o' in 'normal'.....actually it rarely exceeds the 'n'. it's been cool here in Co Springs,
keeping the temps down...I'd like it run hotter....I think I will check the thermostat next.

Also, still only get boost up to 9psi. someone said to check the wastegate actuator....what is the best way to do this?
I have removed the boost control solenoid from the system...and have a manual one in place now, .. opened 10
turns. I'll check the boost output with this new 10 turns when I get home today,....ie take the car for a ride and punch it.
And I also heard there is a fuse behind the premium (gas) toggle......is there for real?

[svono50]

Thanx on the engine compliment, 22 years has given me a lot of winters to play with cleaning.

Interesting you are still getting an ECT code with the new sensor along will purring like a kitten. Nobody ever accused our EEC's of being 'smart'. My car is somewhat similar, when temps drop into the 50's it rarely reads above N on the gauge. Even during a 20min track day session in 90+ deg temps it won't rise over R, but I run straight water and Redline water wetter, no glycol. Our dash gauges are notorious for being inaccurate, so getting the real temp should be left to an aftermarket setup. There are actually 3 temperature sensors on our engines, 1 for the EEC, 1 for the gauge and 1 for the cooling fan. Checking your thermostat is pretty easy if you have a thermometer you can put in a pan on the stovetop to see when it actuates. Stock thermostat is 192 deg and I think there are 185 deg units available, but no 160's like the V8 guys can get.

Best way to test the actuator would be to get a Mity-vac pump that can also supply pressure. You would connect it to the wastegate inlet and bring up the pressure slowly. The gate should open at or very near 10psi of pressure if it is working properly. The way our cars get higher than 10psi is 'masking' pressure from the wastegate inlet to allow the wastegate to remain closed longer. If your wastegate spring has become 'weak' then it could allow the flapper valve to open up to bypass the turbine wheel, which would result in lower than normal boost. One method to check this is to disconnect the wastegate inlet air signal...WARNING, this means your turbo could sing slightly out of control if you keep your foot into it and pop a head gasket, so extreme caution is needed during this kind of test!

No fuse behind the premium switch that I am aware of, it is a direct line to the EEC that I know. All that it does in Premium mode is allow full boost and gives an extra 3 deg of total timing advance over the Regular setting. Hope this helps and let us know what you come up with.

[red766]

it's running fine now....... having replaced the ect, ignition wires, spark pluge, the ECT, ignition coil. Still get bad codes on the scanner, but I'll ignore
them for now.... will double/triple check them in another month.

AND, my booooooost is up to 14 +++. I bypassed the bcs altogether, even bypassed the manual one I bought..so I have a straight tube where
before it went to the bcs (the factory one or the manual one),...so no boost control at all. I know, I had better watch the gauge....I won't go over
14 which is right in the amber zone on the gauge...... Love the increase in speed right away...... Will probably need a clutch someday,....soon.

Next step, replace the fuel filter, and the door pins on both sides...... doors hang about 1/2 inch.... oh, and I had the front hood painted (9L), and
I blackened the pattern on the scoop portion of the hood. And I put '94 style mustang 5 spoke wheels on it........

[svono50]

Glad to hear it is running good for you know, would be good to know why it is still throwing some codes. Just keep a close eye on things. If you run a straight boost signal to the wastegate you should be limited to just 10 lbs, of course the factory boost gauges aren't 100% accurate either. If you don't have anything connected to the wastegate and are only getting 14 lbs then your wastegate is being opened or stuck partially open.

Let's see some pics of your recent work, sounds like it should be looking much better.