88naFC

I have an 88 SE whose engine died of overheating when the water pump seized, throwing off the fan belt and (obviously) causing the wp and alternator to not work. My mom was driving the car at the time, didn't notice that the wipers were slow, etc, and ran the car hard. After it was parked, it never did start again.

Shortly thereafter, I took the car to my nearest (50 minutes away) Mazda dealer and had them check it out. They claim that a compression test revealed that both rotors had zero compression due to warping of the housings and the rotors themselves. So there the car sat for 10 months, as I suddenly became unemployed and due to extraneous circumstances I didn't have the money to get the car from them for that time. I got it back about 2 weeks ago, and got an engine out of a friend's wrecked '86. I rode in his car when it still worked, so I know it was good then, and he and his ex claim that the engine still ran fine afterwards (just that the car couldn't be driven due to the damage to the whole rear of the vehicle). I believe them, but now that the swap has been made, I cannot get the darn thing to start for the life of me. I have checked everything in the haynes manual, and nothing works. When you turn the key, the starter makes its nifty starter noise, and seemingly healthy exhaust pulses can be heard out the back, so I think I have compression, but I can't be sure. I don't know why it wouldn't have compression, I just can't think of anything it could be.

I've replaced the plugs, added a quart of Castrol GTX 10-30, and checked that the housings are getting fuel by seeing gas shoot out the after-filter fuel hose. The plugs are indeed sparking, but the spark is weak looking and orange. Then again, when the car ran before, I didn't look at the spark outside of the vehicle, so I don't know what color it is supposed to be. All my piston-powered friends say that their sparks are violently white or painfully bright blue.

The computer was taken from the 86 also, and the whole thing is ready to roll as far as I can tell.

Any ideas?

Thanks.

HAILERS

Injectors in a 86 are low impedence, 3ohm. The 88 are high impedence 12ohm. Swap the injectors from the burnt up engine into the 86 engine that is in the car. Might work. Might not work. Could have damaged the ECU in a worst case scenario. Edit.....to prove that the injectors are not working, pull the spark plugs. Turn the engine over for fifteen to thirty seconds. While it was turning did you get a fuel mist out the plug holes. Should be an obvious mist. Not *I think I see a mist of fuel*

HAILERS

To see what the resistance is of your injectors, just pull one of the secondary injector plugs off and put your meter on the two prongs of the injector. If it read close to 12 ohms its probably not the injectors. If it reads 2-3 ohms, you probably have the wrong injectors and should swap them with the old engine. Best I can remember, Ted said somewhere in the 87and half and on , they are 12ohms.

88naFC

I had been wondering about the injectors, but could that alone be keeping it from starting? This morning I got some starter fluid and tried that. We took out the air filter and sprayed the starter fluid in the hole in the bottom of the air box, and it made a noticable difference, the engine turned over faster -- but still never started, not even a little bit.

I can't afford a compression test (done with that $3K unit dealerships have), and I can't use the method described in the Haynes because it says I need to have the engine at normal operating temperature. Personally I don't see how temp matters for the purpose of noticing air pressure, but whatever.

If you think the injectors really could keep it from starting at all I'll take the throttle body off and look at them.

I really appreciate your help.

Brian

HAILERS

The wrong injectors, how do I say this, WILL, keep the car from running. You can get easy access to the secondary injectors. Just remove that black inake duct and walla, there she is. Take the injector plug off. If you do not have a meter, go to Radio Shack and get one. You should get a digital meter if you want to play with this car, but for this one time thing you could use one of their fifteen to twenty dollar jobs. Just wanna read ohms today. Your 88 model uses the 12ohm injectors. If the ones in the car are 3 ohm, then swap them for the ones that came out of the original motor. Hey, why not take that meter and walkover to your old motor and ohm out the injectors on it and compare. Also go to the search engine on this site. Put in for a name HAILERS, now look for an item written by DR Swithch. He had a problem similar to yours. A word of caution. Somewhere, I know not where, gave me the impression that if you put 3ohm injectors in a 12 ohm system, that you risk zapping the ECU. Could be true, Could be old wives tale. Keep your eye on the key word in this post. Its the ninth from the beginning and starts with W and ends in L.

HAILERS

Do you still have the old injectors? Do not take the intake until you comfirm that the secondary injectors are the right or wrong ones.

HAILERS

*Fuel injectors clogged?* was the name of the post by Dr. Switch, and his problem is virtually identical to yours. There were two Items by Dr. Switch under the search engine using HAILERS.Both related to injectors. Read the answer by ReTed. Do not wear your battery and starter out until you check the ohms resistance. Now that I've made my daily quota of words, the problem will be something elses totally unrelated.

88naFC

I wasn't using the 88's ECU. I've got the ECU from the 86 installed. The whole 86 engine is installed in the car, so there shouldn't be any incompatibilities between 86<->88 parts as far as injectors and ECUs go... Right?

88naFC

Also, what color is the spark supposed to be? Mine is orange, and to my piston-powered friends, quite weak.

Any info would be of great assistance.

Thanks

HAILERS

There is a key element missing here. Even though you are using the 86 ECU there is something called a resistor pack(I'm at work now, Sunday, and can not look up the correct name). Its located below the airfilter assy. Its about four inches long and bright and shiney, aluminum. It has a large round plug going to it. I'll bet even money your car does not have this plug(the 88). Go look at the 86 the motor came out of and you WILL see it. It is required for flight. HAVE YOU taken a look at the injector(secondary) and checked the ohms? The 86 REQUIRES THE RESISTOR ASSY AND THE 3OHM INJECTORS.Did you earlier take the plugs out and check for a fuel mist? This seemingly small difference of 3ohm vs 12ohm makes or breaks whether the car starts. Did you read the post by Dr Swithch and how this solved his non starting car? Have fun. Go to fc3s.org for the factory manual or to http://www/iluvmyrx7.com and download section 4A of the manual. Fuel section. 12ohm vs 3ohms, gotta have the right car.

88naFC

Ok, I've checked everything except metering the injectors themselves as I won't have access to a meter until tomorrow when I can borrow my friend's Fluke Automotive Meter (should suffice for my needs)...

When I took out the plugs and turned it over it did mist out a whole hell of a lot. Actually I thought it was just air at first picking up the dust in the engine bay and blasting it in my face, but no, that's gas fog. But a point of interest is that the fog only came out the leading (lower) holes. Is this supposed to be the case? When I plugged just those bottom (leading) holes with the plugs still nothing came out the trailing holes. Should something be coming out of there?

I found that resistor pack you mentioned and attached it. It is now firmly bolted in place. Nice of Mazda to leave the holes from the earlier models there so I could just remove the plastic plugs and use the pack... =)

There are a couple harnesses that don't seem to have anywhere to connect. My perception that this is the way they're supposed to be is confirmed by the fact that they're all green, and I think I remember someone saying that all the green plugs are diagnostic ones. I'm not too worried about that though.

I really appreciate all your help, and I'm pretty confident that we're going to get it figured out, it's probably something that should be obvious but for whatever reason I'm overlooking it.

And that spark. Should it be orange or white/blue?

HAILERS

The fuel mist that is coming out makes me have self doubts about the injectors being the wrong ones. If the injectors were not working I figure no mist would come out. I'd still look and see if the injectors are the 2-3 ohm ones because you are using the 86ECU. Almosts sounds like just a case of flooding more than anything else, or a large air leak somewhere. Hose off? Missing? Something I do not understand is the bolt in of the resistor pack. You mean on the 88 car there was a plug on the harness for it? I figured there would be no plug there to attach the resistor. Hmmmmm. And the 88 ran without a resistor pack? hMMMMM. Interesting problem. Better you than me. Humor.

88naFC

Yeah, what I meant about the bolt-in was that on an 86 car there are two holes in the wheel well sheet metal that the resistor pack mounting bolts go through. What I was happy about was that in the 88, since it doesn't use (apparently) the resistor pack I expected the holes to not be there but they are. They're simply plugged with little black plastic pieces so that the owner of an 88 won't think something is missing.

The fact that the holes are still there simply means that I could (and did) simply remove the little plastic plugs from the holes and use bolts I had to mount the resistor pack I removed from the '86 car.

Also, we're pretty sure that the hoses and harnesses are done correctly and everything is as it should be, with one exception that we can't figure out, but it doesn't seem like it should affect the ability to start the car. There is a medium sized white harness plug next to the plug that attaches to the security system light by the e-brake. Since the console plastic (the storage box) is missing, we have no idea what that plug is supposed to be attached to, but we imagine that it is in the haynes or documented somewhere else. I was planning to look at that tonight, as well as testing the ohms of the injectors.

I'm pretty sure that since the donor car was running before I got the engine, that the injectors are correct. I've kept almost every piece that the engine could attach to off that car (the 86)... I can't imagine where any incompatibility could be coming from.

But then again, nobody here knew about the resistor pack for the earlier FC's until you mentioned it.

And is the spark supposed to be orange or blue/white?

Thanks...

HAILERS

Just curious. Which engine harness do you have in the 88 car with the 86 engine? The original 88 harness or did you take the one out of the 86 and put it in the 88? The spark? I'll look tomorrow. Memory serves its blue white. Usually just pleased to have a spark.

88naFC

I'm using all the original stuff from the 86 engine.

Sorry for the delay in responses, but in the time since my last post I've gotten it started. As it turns out, the whole thing was REALLY flooded. We determined this and fixed it by disconnecting the fuel pump in the rear of the vehicle as the remove-the-EGI-fuse-that's-in-the-engine-bay trick didn't work for me, the fuel kept pumping. But now I know of a couple things we need to do.

I'm currently in the process of installing the fuel cut off switch at the little black boxy thing near the steering column as described in another thread somewhere else (I came here to look for it), and I'm confident that once that's done (correctly) I'll be able to start the car easily.

The timing seems a little off, as the car won't really idle on it's own. I'm going to clean off all the fuel buildup off the plugs first before I adjust any timing stuff just to be sure, but we'll probably have to adjust it a little bit.

Anyway, I have to drive the car to work tomorrow at 6:30AM, so I plan to do whatever is necessary to get it running nicely/smoothly tonight. I'll post my findings when I find them.

Thank you for all your help, without it we wouldn't already be where we are in the process of fixing the car.

88naFC

Well, it's official. The car runs great!

Once we realized it was flooded we installed the fuel cut switch, and it started right up. Also, the timing was 2 teeth off (!), so that was fixed and it's all beautiful now.

There are a couple more issues I'd like to address, but I'll stick around the forum and become a productive member of the RX-7 community.