Hey all. So I have a 1987 Ford Country Squire. It is my daily driver, and man, do I put the miles on it. I am a teacher, so since summer has officially begun, we decided to do an engine swap. Nothing fancy. We just had another 302 that we cleaned up. We put some E7 heads and a new cam in it (the cam has since been swapped to the original because we were concerned that was causing the issues). We have replaced the distributor, the air charge sensor, the ignition coil, the MAP sensor, spark plugs, and the IAC. Compression checks were ok, 175 +/_4. Vacuum checks were ok, 16-17. Fuel pressure checks were ok, 30 idle 42 acceleration. Injectors were ok, all between 14 and 16. The problem comes with accelerating from a stop. It will feel a little low on power and then it makes a little puff. It's not a backfire. We are struggling to figure out what is wrong with it. Anyone have any ideas on what to look at next? We would like to avoid going to a mechanic because we don't have a lot of money.
Vac is low, 18 is the minimum you want, and should be 18-22". Because your CS is fuel injected, any vac leak affects the MAP, as well as leaning out what fuel the computer does let into the engine. You need to do the old 'tried and true' method of finding vacuum leaks by spraying carb cleaner along the lower intake sides, both sides of the lower manifold/upper plenum attachment, and the throttle body, EGR valve and spacer. Then, you need to verify that all vac lines are plugged in and intact, not split, including the PCV line and valve. There isn't much as compared to a carbureted engine to check, but it is much more important. Let us know what you find, I am a Mech/tech, so if you have questions, you are more than welcome to PM me.
So we blocked off the EGR and I drove it for 15 minutes and there was no misfiring. It seems like my problem may be in the EGR.
What is the initial and total timing set at, and have you checked the plug wires? I didn't see them in the list above with teh plugs, distributor replaced, etc.
We changed the wires last night. We had gotten new ones when we first got it started last year, and so we didn't replace them right away. Our timing is set at 10. My husband took out the egr and blew through it and sucked on it. We think it may have been stuck. We ordered a new one which should be here today. If it isn't the EGR, I was thinking one of two things. The first is the injectors. The second is a weird wiring issue. When we got this car, there was a lot of stuff not hooked up. There are also two wires that have been cut and are just hanging out. We were on the phone with Ford trying to get a wiring diagram, but they weren't able to find one. One wire is red and the other is white. My money has been on those two wires, but we can't figure out what in the heck they were suppose to connect to. I love my wagon so much. This is driving me crazy.
Okay, first off, injection will not cause lower vacuum, but a stuck open EGR, at idle and throttle tip-in, will cause rough idling and lowered power accelerating from a standing start. Ignition, when properly set, will not cause lowered vacuum whether the SPOUT is plugged in or not. So, once the EGR is installed, verify there are no vacuum leaks anywhere else, including the EGR spacer itself.
I wouldn't go crazy over just two wires. Those are the clues to follow. Therefore, that would be the first place to start looking, since it's a wrong to set right. I'd follow them and first connect them to where they belong, before doing anything else. As far as identifying these wires through color, it seems the more information there's out there, the more it's hidden. This is the closest I've arrived at: https://www.wirediagram.com/linkpage/VICTORIA_FORD_CROWN_ 1987 2DR SEDAN_wiring_information.htm For some strange reason, there is no shortage of information regarding pick-up trucks and Broncos of that era. Perhaps, the best way would be to visit a wrecking yard and start looking there for a full-sized Ford of that era. If Ford even uses a uniform wire code is still a mystery. Joining a Ford club can't be the worst way of finding out
When a car idles fine and sputters and misfires like this on acceleration, my experience has always been timing issues. The timing is too far retarded, specifically. Either the initial is set too low, or the mechanical\computer advance is not operating like it should when you give it pedal. EGR being stuck will cause a super lean condition and backfiring, but if the EGR valve is stuck it will do it at idle in park too and not just under load.
Red and white? Did the car come with automatic air conditioning? It may have gone to the automatic heater control valve. Are the wires on the rear passenger corner of the engine, along with a couple vacuum lines?
I believe these engines had PVC hoses under the upper intake manifold. You may want to have someone pull the upper intake and inspect all the hoses under it.
The vacuum control lines could be a leak source; look specifically at the red lines (manifold vacuum), but also look under the upper plenum, as the MAP vacuum line, and the EVAP vacuum source, both hook up underneath it, as well as the PCV line.