Everything works fine except after 10 minutes or so on the highway at 70mph, the check engine light comes on. Stop and restart the car an all is well. I can drive around town and no light until I hit cruse mode on the highway. Did a little reading and discovered it could be the EGR control solenoid. It could be as simple as a vac line too but I'll sort that out later. So just out of curiosity I went looking for the cost of a new control solenoid and there are none except a guy on eBay who wants $560. If mine is bad, can it be fixed? Is there a resource I'm missing for a replacement?
A lot of vehicles used EGR solenoids like the Ford F150 of he 1990's and they are inexpensive. . I see no reason why they cannot be used on a Fiero.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
The 2.8L engine has an EGR solenoid which is actuated by the ECM to open the EGR valve. The EGR solenoid is mounted on an engine bracket near the battery and the EGR valve is mounted on the exhaust pipe near the distributor. The solenoid is unique to the Fiero and was not used on other vehicles. The part number is AC Delco 214-361 and is generally available, although pricey. We understand that EGR solenoids from late '80s S10 trucks can be substituted but since they are not same mounting or configuration, some "engineering" is required.
Fierosound, thanks for the links. Better info than I originally found.
Not new to Fiero but I've been away for about 28 years. Had an '85 for a few years way back when and recently bought an '88 GT about a year and a half ago. It and I will be in the garage today listening to music together and looking at the vac lines and testing the solenoid. I did look up the vac solenoid for an '88 S10 with the 2.8l motor and it looks to be an easy install. Best part is that they are available and about 1/6 the cost of the one on eBay. One question though, while S10 has a 4 pin connection, it only has the two vac lines that go to the intake and the EGR. What about the vac line that goes to the air cleaner? Just not necessary?
Before assuming that the solenoid is bad, look at the less expensive EGR valve, itself. To test it, if you have a MightyVac tester, pull a light vacuum on the valve to see if you have bleed-down. If you don't have a tester, pull the vacuum line from the nipple, and with a cold engine (so you don't burn your fingers), press up on the diaphragm from underneath. Cap the vacuum nipple with a finger and while keeping your fingers in contact with the diaphragm, note if the diaphragm leaks down. It could simply be a hole in the diaphragm. You can test its vacuum line for leaks in the same manner by disconnecting it at the other end, depress the diaphragm and cap the end of the line.
That little loop of plastic line on the solenoid can be a source of your code, too. The rubber sleeve is probably rotted and can leak. I replace the little sleeve with some vinyl aquarium tubing and have also used the tubing to make a connector joint where the tubing is broken, and I've even replaced the whole piece of plastic tubing with the vinyl tubing.
[This message has been edited by fierofool (edited 11-24-2018).]
Fierofool, took your advice and tested the EGR while I was playing around in the engine bay. Pulled a vacuum on the EGR nipple and it opened and stayed open. So I got that covered. Also checked the small loop on the solenoid and it was good.
I did find a loose hose from the solenoid to the air cleaner. The one that sticks out by itself and goes around behind the motor. It wasn't detached but it was barely on. It's also a piece of fuel line. I'll be replacing that with some nice vacuum hose. Also found the rubber 'T' that is connected to the intake manifold behind the MAP in kind of bad shape. Only half pushed on with some cracking showing at the opening that connects to the manifold. I'll be looking for some mew Vacuum bits to make sure this is all good.
My main concern about the solenoid valve wasn't' that I think it's bad. I was just expressing concern if it does go bad and there are no replacements...……..then what?
Still interested in feedback on the S10 solenoid. It doesn't look like it has the hose to the air cleaner and wondering if anyone has done it yet.
This possible replacement appears to have a built-in filter, so no intake line to the Fiero's air cleaner would be needed. Still, it would be a good idea to compare the new unit's coil resistance to the original's before fitting it. It would be interesting to see if this unit would be a good replacement for our older part..
The CEL isn’t necessarily set because the EGR isn’t working but because the (very expensive ) controller isn’t working.
You can run a vac line directly to the EGR if you feel the need. You’ll still get the CEL, but for the most part you’re doing all you can do considering you’re driving a 30 year old car with replacement parts more expensive than the resale value of the car.
I’ve done every variation of reroute, replace, redo there is and couldn’t detect any difference in performance, but the CEL comes on after some period of time.
I took out the defective controller and just rerouted everything. I get the light but put my Bluetooth mic over it and just enjoy driving my SE.
The earth is not going to come to an end because my EGR isn’t perfect.
Check my sig before you take my advise.
------------------ FWIW, YMMV, EIEIO '86 SE, '95 XJ6, '73 C104
Just a quick update. The Fiero Store will sell me a refurbished, tested etc. EGR Solenoid for less than half of the one on eBay. Jeremy and the guys there were easy to deal with and very accommodating. Great guys.
I know, I know, lots of folks can ignore the check engine light or even remove the EGR with block off plates but I can't. It's a personal thing, but for me, everything on my car should work like new and that includes the EGR system.
Look at the photo of the EGR Solenoid, the big drum shaped piece on the right is a built-in air filter. The port on that side is a vent that let's atmospheric air pressure into the EGR vacuum line when the solenoid is off. So air flows from that port, through its filter, and to the EGR vacuum line to fill (release) the vacuum with air. I just found out the rubber hose from the vent goes to a thin steel tube against the fire wall, that tube goes over toward the air cleaner (but not in in) to draw in cooler air into the solenoid rather than the air surrounding the solenoid which is much hotter.
The Fiero Store just told me AC Delco has discontinued the EGR Solenoid. I am going to make my own with a two way air valve, a small air filter, and a vacuum switch. It won't look the same but it will be better than the OEM solenoid.
By the way. I am reading 7 Meg Ohms across the Solenoid Input pins. I get infinite Ohms when I reverse the leads. Is this correct? Is it a simple solenoid control or is there more electronics inside it? That high resistance seems to indicate a digital input, and not a solenoid coil (around 50 ohms).
The other two leads are good: Open (Infinite Ohms) with no vacuum. Short (0 Ohms) with vacuum present.
Does anyone know exactly what signals the ECM sends to the EGR Solenoid.
The solenoid like most relays likely has a diode to kill power surge when power is turn off. ECM simply switches solenoid to ground same as does fuel injection.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
