QuestionEngine, performance, and drive train issues, 1990 Eclipse.
I have several questions that pertain to my aging
1990 Eclipse with the 4G63T engine and a manual 5 speed.
This engine and the car have about 175K miles, about
70K on its second turbo.
Q1. The car feels a bit sloppy with too much body roll
in turns. I plan on replacing the towers. What is the
expected life on the springs? Should I replace those as
well? What about other front or rear suspension components
that need replacing?
Q2: The engine (actually the controller) has trouble idling
if started at an intermediate run temperature. This started
after the spark cables were replaced at the dealership. Any
ideas? Once the engine heats up a bit, its ok. It seams
like the controller is trying to run the engine closed loop,
when its too soon. Note: The controller does not respond to
throttle position when in this mode.
Q3: Its getting hard to get performance out of the engine.
The plugs show oil burn, and I think that the valve seats
are irregular. It responds well to injection cleaners, and
BG44K, however I have been thinking about either a JDM or
rebuild. Most of the troubles appear to be in the head. Do
you think it would be wise idea to have the head rebuilt,
and only re-ring the pistons? How about a top and bottom
rebuild in place in the car versus a JDM? How many shop
hours to a)Pull and reinstall head. b)Rebuild engine face.
c)Rebuild engine bottom.
AnswerNick,
All good questions. I'll answer them in the order you put them in:
A1. The life of your springs should last the life of your car, depending on your driving style, amount of driving, and road conditions. If you're looking for a tighter suspension, I would recommend replacing your front struts and rear shocks, as well as a good set of 4 springs. I would not recommend going too low with new performance springs because that will put excess stress on other suspension parts. Even when lowering your car only an inch or two may also require a new alignment kit. You should also consider front and rear tower braces for your car. Those are cheap and you can get both on ebay. Other than that, you could replace all your suspension bushings, but that is expensive and very time consuming.
A2. After 175k miles, it would not be uncommon for your Idle Air Controller to start to fail. The IAC for the 90 Eclipse is different than any other year of Eclipse, so it's a bit expensive. Any service manual will give a procedure how to test your IAC, so you can test it directly. If you need to replace it, you may want to look for a used to save some money. You may also have luck cleaning your throttle body and other intake components. You can even pull your intercooler and clean that out.
A3. It's tough to guess if swapping your engine with a JDM engine or simply rebuilding would be the better deal. A JDM engine can give you a little more problem, but may bring up different problems. Unless you hear consistent rubbing/grinding noises coming from the bottom of your engine, I would think the bottom of your block is ok. If it were me, I'd most likely just rebuild the head and replace the rings. With a head rebuild, you can have your head shop provide a five angle valve job, along with replacing all seals and guides. For additional performance increase, you can replace your cams; particularly your exhaust cam if you can't budget both the intake and exhaust. And since you need to remove the timing belt, you should replace the timing belt, balance belt, and auto tensioner if you haven't within the past 45k miles. I would also recommend replacing balance shaft oil seal and front crank oil seal as well.
Good luck!
